If I am a Christian, do I have to ask for forgiveness for every time I sin?

This is a great question. A verse that talks about this is 1 John 1:9: “If we confess our sins, He is faithful and just and will forgive us our sins and purify us from all unrighteousness.” This verse says that we should confess our sins and that God will forgive us. Confession is different from asking God for forgiveness. “Confess” means “to agree with”—it means that we agree with God that we were wrong and that we have sinned. God then forgives us, because He is faithful and just.

On the other hand, salvation is not a matter of Christians trying to confess and repent from every one of their sins before they die. Salvation is not based on the confession of sin. And yeah, we should confess our sins to God. But when we place our faith in Jesus for our salvation, all of our sins are forgiven—that includes past, present, or future.