Romans 4:21 Meaning: Fully Persuaded of God's Power
and being fully assured that what he had promised, he was also able to perform.
And being fully persuaded that, what he had promised, he was able also to perform.
and being fully assured that what he had promised, he was able also to perform.
and having been fully persuaded that what He hath promised He is able also to do:
and being fully persuaded that what he has promised he is able also to do;
Meaning in one sentence
In Romans 4:21, Paul describes Abraham's faith as being fully assured that God can do what He promised. This trust is the essence of saving faith.
Context
Paul is making a case that Abraham, the father of the Jewish people, was justified by faith long before the law or circumcision. In chapter 4, he walks through Abraham's story from Genesis. God promised Abraham a son when he was about a hundred years old and Sarah's womb was dead. Humanly speaking, it was impossible. But Abraham did not focus on that. Instead, he grew strong in faith, giving glory to God. This verse is the climax of that description: he became fully convinced that God had the power to deliver on His promise. Paul wants his readers to see that this kind of trust is what makes faith saving, not merely believing facts, but relying on the person of God.
Key Words
Two Greek words carry the weight here. The first is πληροφορηθείς (plērophorētheis), which Vincent's Word Studies says means 'being filled with a thought or conviction.' This is not a weak hope or a wish. It is a confidence that fills the soul so completely there is no room for doubt. Abraham did not just think God probably could; he was fully persuaded. The second word is δυνατός (dunatos), translated 'able' but stronger. It means mighty, powerful, capable of doing the impossible. Thayer notes it can describe someone strong in soul to endure trials with patience. Together, these words show that faith rests not on our own strength but on God's power. When we trust a promise, we are leaning on the One who is mighty enough to keep it.
How Christians Read This Verse
Christian readers across traditions have seen this verse as a window into the nature of faith. Reformed commentator Calvin observed that while everyone acknowledges God's power in theory, nothing is harder than to truly ascribe to it the honor it deserves when obstacles arise. The Cambridge Bible notes that faith here is not mere historical belief but personal trust, looking away from self and resting on the divine Promiser. Methodist scholar Adam Clarke emphasizes that Abraham's soul was 'full of confidence' that God's truth and power together guarantee the promise. Baptist writer Gill points to Abraham's 'full assurance of faith' resting on God's omnipotence. All agree: this kind of trust gives glory to God and is the heart of the faith that justifies.
A common misunderstanding
Some read this verse and think that if they are fully convinced enough, God will do whatever they ask. They treat faith as a force that compels God to act. In fact, Abraham's faith was not a general positive attitude but a specific trust in a specific promise God had made. The point is not that we can manipulate God with strong belief, but that we rest in His character and His word. The power belongs to God, not to our faith itself.
Living This Out
This week, you will face something that seems impossible, a broken relationship, a financial shortfall, a health concern. Your instinct will be to look at the problem and feel hopeless. Instead, you can follow Abraham's example. He considered his own limitations but chose to focus on God's ability. Take one promise from Scripture, that God works all things for good, or that He will never leave you. When doubt creeps in, remind yourself: 'God promised, and He is able.' Let that truth fill you until there is no room for fear.
Main takeaway: Saving faith is being fully persuaded that God has both the will and the power to keep every promise He has made.
For Families
For ages 5, 8
God promised Abraham a son, even though Abraham was very old. Abraham believed God could do it because God is strong enough to do anything. You can trust God's promises too, He always keeps His word.
For ages 9, 12
Abraham was almost 100 years old, and Sarah was past the age of having children. But when God promised them a son, Abraham did not focus on how impossible that seemed. He was completely sure that God had the power to do what He said. That is real faith, not just believing facts about God, but trusting Him personally to keep His word. When you face something hard, you can have that same confidence. God is able, and He always does what He promises.
Questions People Ask
What does 'fully assured' mean in Romans 4:21?
The Greek word πληροφορηθείς (plērophorētheis) means to be filled full with a conviction. It is more than intellectual agreement; it is a deep, personal certainty that fills the whole soul. Abraham was not hoping against hope, he was completely convinced that God would do what He said.
What promise is Paul referring to in Romans 4:21?
Paul is referring to God's promise to Abraham that he would become a father of many nations, specifically that Sarah would bear a son despite their old age. This promise is recorded in Genesis 15 and 17. Paul uses it as an example of how faith works: trusting God's specific word against all human odds.
How does Romans 4:21 relate to justification by faith?
Paul is showing that Abraham was declared righteous not because of his works but because of his faith. Verse 21 describes the quality of that faith: full assurance in God's power. This trust itself is credited as righteousness. So the verse teaches that saving faith is a confident reliance on God's promise, not a vague belief.
Does Romans 4:21 mean we must never doubt?
The verse describes Abraham as being fully assured, but it does not say he never had questions. Earlier in Romans 4, Paul notes that Abraham considered his own body and Sarah's womb. The point is that he did not allow those obstacles to weaken his trust. Doubts may come, but faith chooses to look to God's ability rather than the difficulty.
For pastors & researchers
Greek interlinear, 8 commentaries & word study