Old Testament prophetic scriptures about the coming Messiah spoke of it in terms of the past “out of the land of Egypt” to the future “they shall again live in their own land.” (Jeremiah 23)
The actual story of the birth of Jesus in Matthew tells us of Joseph’s dilemma with the past. The Bible gives us specific information about Joseph. Joseph was a righteous man. He did not want to shame Mary (he could have had her stoned). We have the angel speaking to Joseph in a dream. He is told not to be afraid. He is told to marry Mary. He is told to name the child “Jesus” because “he will save his people from their sins.” The angel quotes the prophetic Isaiah scriptures to Joseph. When Joseph awoke he did as the angel commanded him.
Joseph did not dwell on the past. He never had to question Mary’s virginity or her faithfulness to him. He had confirmation from an angel of God and that was enough. He believed and he named the baby “Jesus”.
Most of us live with some guilt from our past. We have never had an angelic meeting to help us move forward and help us not to dwell on our past. But we have so much more. We have Jesus. This child that Joseph named Jesus came as that perfect son of God to earth to save us from our sins. He forgives us of our past and we can move forward with as much assurance as Mary and Joseph did over 2000 years ago. The past is the past but the future is so much better.