Introduction

Without question, two of the most precious truths the Protestant Reformers recovered were the doctrines of eternal security and assurance of salvation. Afterall, the church taught that assurance is impossible. So, everyone assumed you can’t know for certain you will be in heaven because there’s always the possibility that you will fall short or commit a mortal sin and lose your salvation.

So, although everyone called God their Father, they were never quite certain that he was their Father. This fact dramatically affected how they related to God, worshiped God, and served God. It’s hard to have a close relationship with someone when you are never sure how secure the relationship is.

But the Bible teaches that God will certainly keep all his children. Jesus promised, “My sheep hear My voice, and I know them, and they follow Me; and I give eternal life to them, and they will never perish; and no one will snatch them out of My hand” (John 10:27–28). Christ will save all his sheep.

And God wants us to be sure of this fact. He doesn’t want us to constantly wonder if we are his children and if we will make it to heaven. Instead, God wants us to know that we have eternal life (1 John 5:13).

That’s important because insecurity erodes any relationship. Your marriage will never thrive if you question your spouse’s love. Children can’t thrive without knowing their parents love them. A team will struggle if it’s members don’t know they have each other’s backs. Strong relationships demand security.

Therefore, eternal security and the assurance it brings are precious doctrines for  healthy faith. So, it’s a good thing we are in Romans 8 because this is the preeminent NT passage on these doctrines. And today’s passage is especially important to enjoying assurance of salvation (read). This passage is all about the Spirit’s work to assure us of our salvation. Notice first…

I. The Spirit leads (v. 14).

Verse 14 is a transitional verse, and it is closely connected to v. 13. God says that everyone in whom the Spirit dwells will “put to death the deeds of the body (i.e., sin).” And they look forward with certainty to the promise that they “will live,” meaning they will live with God in heaven for all eternity. So, the point of v. 13 is that the Holy Spirit’s presence assures me that I will persevere in right doctrine and in right practice and that someday I will reach glory.

And v. 14 reaffirms this confidence (read). We must consider what it means to be “led by the Spirit” because many Christians use this sort of language to describe some kind of mystical direction to help with decision making. They want the Spirit to lead them to the right college, or spouse, or career.

God certainly cares about these things, but they are not his concern here. Rather, Paul has been talking about how the Spirit sanctifies God’s people; therefore, v. 14 describes how the Spirit leads us into godliness.

The thought is similar to leading a horse. If you turn right, it follows. If you go straight, it follows. The horse follows your will. Similarly, a person who is led by the Spirit is following the Spirit’s lead toward godliness. He is striving to obey the commands and priorities of Scripture, and Spirit empowers his success.

It’s an encouraging picture because holiness can seem overwhelming. But God hasn’t left us on our own. The Holy Spirit is with us, leading us along, and helping us grow into Christlikeness. So, follow his lead, and watch him help you “put to death the deeds of the body.”

And notice that as he does this, we receive assurance that we are “sons of God” or genuine believers. So, God wants you to recognize his sanctifying work and draw assurance from it. That’s important because sometimes, we don’t notice how the Spirit is changing us. We only see our problems, and we are discouraged. So, make sure that you step back and notice his work.

Then be assured that you are a child of God. We use this sort of familial language often, but I hope we never take it for granted. We aren’t merely God’s slaves, and we aren’t merely citizens of heaven. We are sons and daughters of God. We are his children.

I love how 1 John 3:1 contemplates this incredible reality when it says, “See how great a love the Father has bestowed on us, that we would be called children of God; and such we are.” The fact that Holy God would adopt sinners like us is so amazing that John felt the need to add, “and such we are.” It’s really true. It’s amazing that God is our Father. And v. 15 expands on this incredible truth and describes how the Holy Spirit assures us that it is so. Not only does the Spirit lead; the Spirit also comforts.

II.  The Spirit comforts (v. 15).

Verse 15 paints a beautiful picture of our relationship to God by contrasting “a spirt of slavery” with “a spirit of adoption.” I’ll go ahead and mention that “spirit of adoption” should be capitalized because it’s clearly referring to the Holy Spirit.

However, “spirit of slavery” should remain in the lowercase because the Holy Spirit doesn’t enslave. No, the fact that Paul adds “leading to fear again” indicates that he is reflecting on the Romans’ pagan past.

Before, they were saved, they served pagan gods out of fear of punishment. That’s how every pagan religion operates. People serve and obey their god, not because they love him, but to avoid his wrath. It is always a master-slave relationship, never a father-son relationship.

Of course, our relationship to God does have some parallels to slavery. Paul introduces himself in Romans 1:1 as “a bond-servant of Christ Jesus,” and 6:18 describes Christians as “slaves of righteousness.” God is our master, and we must obey his will.

However, God is much more than an authority; he is a loving Father. Therefore, v. 15 reminds us that when we got saved, they didn’t simply replace one enslaving religion with another. Instead, “You have received…”

The doctrine of adoption has to be one of the sweetest doctrines in Scripture. The 2nd London Baptist Confession says, “All those that are justified, God (gives)…the grace of adoption, by which they are taken into the number, and enjoy the liberties and privileges of the children of God, have his name put on them, receive the spirit of adoption, have access to the throne of grace with boldness, are enabled to cry Abba, Father, are pitied, protected, provided for, and chastened by him as by a Father, yet never cast off, but sealed to the day of redemption, and inherit the promises as heirs of everlasting salvation.”

Adoption is not slavery. A slave is merely a servant of the master. But an adopted child is a full member of the family, and he enjoys all the privileges of sonship. As the confession says, “God pities, protects, provides for, and chastens (us) as a Father, yet never casts (us) off.”

Consider that. The moment you were saved, God fully received you into his family as if you had always belonged to him. In fact, we are such complete members of God’s family that we are qualified to cry “Abba! Father!”

This is a rather unique form of address that is packed with significance. “Abba” is the Aramaic term for father, and it expresses a close, personal relationship. Paul combines it with the generic Greek term for father.

What makes it significant is not the phrase itself, but who coined it and when he did so. To our knowledge the very first person to use this designation for God was Jesus in his moment of greatest need.

Mark 14:34–36 tell the story in Gethsemane, just hours before Christ’s crucifixion, “He said to them, “‘My soul is deeply grieved to the point of death; remain here and keep watch.’And He went a little beyond them, and fell to the ground and began to pray that if it were possible, the hour might pass Him by.And He was saying, ‘Abba! Father! All things are possible for You; remove this cup from Me; yet not what I will, but what You will.’”

It was a powerful moment that was forever burned into the disciples’ hearts. They never forgot this incredible moment between God the Father and God the Son, and hearing the Savior cry, “Abba! Father!”

And since “Abba! Father!” is how Jesus addressed his Father, how amazing is it that the apostles would now say that God’s adopted children can also speak to God using the same precious language that Jesus used. We are not second-class family members. God has fully adopted us into his family.

It seems almost too good to be true. And particularly when you fail, Satan will tempt you to believe it really is too good to be true. “There’s no way a sinner like me could speak to God on the same level as Jesus.” Sometimes, the darkness of my soul overwhelms the light of God’s promise, and our faith in them grows weak.

And God would be just to turn away in disgust. But, “As a father has compassion on his children, so the Lordhas compassion on those who fear Him.For He Himself knows our frame;He is mindful that we are but dust” (Ps 103:13–14). Our weakness moves him toward us, not away from us.

Specifically, his Holy Spirit enables us to cry, “Abba! Father!” Galatians 4:6 goes even further saying, “Because you are sons, God has sent forth the Spirit of His Son into our hearts, crying, ‘Abba! Father!’” The connection between the two passages seems to be that Spirit makes the cry first, then he enables us to utter it ourselves.

It is so encouraging because God didn’t just provide salvation and give us strength to believe. He continues to strengthen our faith in the promises of Scripture so that we believe in God’s love and the promise of adoption and so that we draw near to God with confidence. We relate to God as our Father.

That’s why I’m calling v. 15, “The Spirit comforts.” Whenever, I cry out to my Heavenly Father, it is not merely an expression of my faith; it is evidence of the Spirit’s work to help me believe what I would never believe on my own—that Holy God would love a sinner like me as his own son.

Praise God for the doctrine of adoption, and praise God for the Spirit’s work to help me believe it and express it. Then v. 16 expands on this work of the Spirit.

III.  The Spirit testifies (v. 16).

I’ve said before that when I was younger, I went through a couple periods where I seriously doubted my salvation. Unfortunately, my confusion about this verse added to my doubts rather than dispelling them.

Specifically, God says that if I am his child, the Spirit will testify to me that I am his child. So, I tried to listen for him. I wasn’t expecting an audible voice, but I was looking for something close to that. I waited for him to zap me with the feeling that I was saved. When I didn’t feel what I was looking for, my doubts only increased, and I became even more discouraged.

I don’t believe I’m alone. Many Christians have wrong assumptions about how the Spirit ministers to us. And understanding this verse is crucial to correcting these problems.

But before we get to all that, we first need to set v. 16 in context. Notice that v. 16 is closely related to v. 15. Verse 15 said that the Holy Spirit gives us confidence to address Holy God as “Abba! Father!” And v. 16 follows by simply expanding and broadening the thought, “The Spirit Himself…”

So, v. 16 explains how the Spirit causes us to make this cry and more broadly how he helps us know we are “children of God.” To put it simply, v. 16 describes how the Spirit gives us assurance of salvation.

Specifically, he does this by “testif(ying) with our spirit.” Again, what is that? My younger self and many, many believers assume that this testimony is anchored in a feeling, that it’s almost a voice, or even a voice.

For example, Pastor Tim, Dustin, and I were at a meeting recently where several people said, “God told me…” They weren’t talking about reading the Bible; they were talking about a feeling that they were pretty sure came from God, though they’d probably have to admit they weren’t 100% certain it was God’s voice. Afterall, I’m sure they have all misinterpreted those feelings before.

That’s the problem with trying to hear from God through your feelings. Our emotions can be very unpredictable because sinful lusts are always interwoven with my feelings.

For example, I’ve heard many believers explain a decision by saying, “I didn’t have peace.” But how do you objectively distinguish worry from the Spirit’s prompting? I don’t believe the Bible encourages us to base our Christian lives off something as unpredictable and murky as our feelings.

Rather, if you want to hear God, read the Bible! God has already provided everything you need for life and godliness in his fully sufficient Word.

And since the Bible is objective, clear, and fully sufficient, we should understand v. 16 as essentially describing the Spirit’s illumination of Scripture. Afterall, where do we learn to cry, “Abba! Father!”? Does it randomly spring out of our feelings? No, the Bible tells us that God is our Father, and the Bible tells us that we are God’s children, assuming we’ve believed the gospel.

So, vv. 15–16 are not describing some existential, emotional, prophetic moment. No, they are describing how the Spirit takes the truths and promises we read in Scripture and causes us to understand them, believe them, and believe they belong to me.

Notice Paul’s prayer in Ephesians 1:18–19, “I pray that the eyes of your heart may be enlightened, so that you will know what is the hope of His calling, what are the riches of the glory of His inheritance in the saints,and what is the surpassing greatness of His power toward us who believe.”

Is any of that new information for the Ephesians? No, it’s all basic gospel truth that is contained in the Bible. The Ephesians didn’t need more revelation; they needed the Spirit’s “enlightenment” (i.e., illumination) of revealed truth, so that it would be planted deep in their hearts.

And so do we. We don’t need more revelation. We have a fully sufficient Word. But we need the Spirit to help us understand it, believe it, and apply it.

So, what do you do if you are struggling with assurance of salvation? And how can all of us grow in our appreciation of God’s love and our security in him? Read the Bible, meditate on the Bible, listen to biblical preaching, and talk to other saints about the Bible. Pay attention to gospel promises and to assurances of God’s love.

As you do this with a heart of submission, the Spirit will illuminate Scripture. He will “testify with your spirit that you are a child of God.” In other words, he will expand your understanding of Scripture, he will strengthen your faith, and he will help you believe that all this incredible truth is not just true; it’s true for me.

Don’t make this complicated and weird. Read the Bible and pray, “Open my eyes, that I may behold wonderful things from Your law” (Psalm 119:18). Then watch God create assurance and mature your faith.

The Spirit’s witness is an incredible ministry. We are all weak but praise the Lord that he has not left us alone to believe his Word. The Holy Spirit indwells us, he keeps us, and he is always expanding our vision of the riches of God’s glory and the surpassing greatness of his power. Give thanks for the Spirit’s testimony. So, vv. 14–16 describe 3 awesome ministries of the Spirit. Finally, notice our response in v. 17.

IV.  The Christian hopes (v. 17).

This is another transitional verse. Verses 18–25 will describe the incredible inheritance that is awaiting us in glory. And v. 17 links our standing as God’s children to this great hope. Specifically, since we are God’s sons and daughters, we are also heirs of his magnificent inheritance.

This fact offers a different perspective on heaven from what we often consider. We will not simply be residents in the city of a great king; rather, we will be sons enjoying our Father’s riches.

And the emphasis of v. 17 is on the fact that we will certainly receive our inheritance because we are God’s sons and daughters. He will not fail. Heaven is just as certainly ours as if we already had it.

Now, Paul does add a qualifier. We are “fellow heirs with Christ, if indeed…” It’s a genuine qualifier. Jesus warned, “Whoever denies Me before men, I will also deny him before My Father who is in heaven” (Matt 10:33). We must remain faithful, though Romans 8 repeatedly states that the Godhead is working together to ensure that we will.

But considering the context, the emphasis is not so much on the qualifier but on the reward at the end of the road of suffering. Following Christ is not easy. The world will hate us, and Christ demands that we lay down everything for the sake of the gospel. But the Spirit will keep us.

And notice the assurance of v. 18. Christ will overwhelmingly reward every sacrifice. We have a great inheritance awaiting us.

Conclusion

Is God our master? Absolutely! Christ bought us on the cross, and we owe him everything. But God has also adopted us into his family. He is our Father, and we are his sons and daughters. And he is a compassionate Father. He remembers that we are but dust; therefore, he gave us the Holy Spirit to assure us of his love. So, we can know that God is our Father. We can rest in his love and strength like a child in daddy’s arms. And we can look forward with confidence to the fact that he will bring us to heaven, and he will keep every promise.

Do you have this confidence? Do you know that your sins are forgiven in Christ? Do you know God is your Father because you understand and believe the gospel? If you need to be saved, we’d love to talk with you about how you can be adopted into God’s family. I hope you will give us that opportunity.

And if you have received Christ, but you struggle with doubts, please get help. You will never thrive spiritually as long as you are questioning God’s love and your standing with him. God wants you to know, and we want to help you find that assurance in the truth of the Scriptures and testimony of the Spirit.