Israel's Sins of Time Past

Explaining The “Sins That Are Past” of Romans 3:25

“[Jesus Christ] Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance [self-restraint or tolerance] of God; (Romans 3:25).

Does the Bible teach here that we are only forgiven of our past sins? What are these “sins that are past?” In this Bible study, we will tackle this most troubling phrase.