I’m having some trouble with Hebrews 10:36. We know that the will of God is to believe on His Son, and the promise is eternal life. I believe OSAS, but I’m having trouble reconciling this verse.
It helps our understanding to take the entire passage of Hebrews 10:35-39 in context.
So do not throw away your confidence; it will be richly rewarded. You need to persevere so that when you have done the will of God, you will receive what he has promised. For in just a very little while,
“He who is coming will come and will not delay. But my righteous one will live by faith. And if he shrinks back, I will not be pleased with him.” (Habakkuk 2:3-4)
But we are not of those who shrink back and are destroyed, but of those who believe and are saved.
The letter to the Hebrews was written to encourage Jewish believers to resist going back under the law and to fully entrust their salvation to the Lord’s once for all time sacrifice. Speaking of that sacrifice the writer said, “So do not throw away your confidence; it will be richly rewarded.”
The perseverance he spoke next of concerns living by faith, which is God’s will for us. John 6:40 says,
“For my Father’s will is that everyone who looks to the Son and believes in him shall have eternal life, and I will raise him up at the last day.”
Then the writer quoted from Habakkuk 2:3-4 to underscore the fact that God wants us to live by faith. And finally he confirmed that going back under the law instead of living by faith indicates that a person who does so was not really saved in the first place.