opusdei1972,
How do we know Jesus or the disciples viewed Adam as a literal person who actually existed?
Jesus always spoke in parables. A parable is a fictional story with fictional characters and is used to teach deeper moral truths.
Since Jesus was so accustomed to speaking about fictional characters, why should we assume that when it came to Adam, He must have viewed him as literal?
Plus, in Galatians, Paul says Sarah and Hagar are allegorical characters foreshadowing the two groups in his day:
1. Early Christians.
2. Jews who opposed Christians.
It was common for First-Century Christians to interpret the Old Testament as allegory.