It began much later as a way of marking time for the Penitents who would be restored to the fellowship of Christians and the Catechumens, who would prepare for baptism at the Great Vigil of Easter. Elijah spent 40 days in the wilderness before hearing the still, small, voice of God on the same mountain where Moses spent 40 days listening to God give the law. The Church announces a season of Lent, an invitation to springtime of the soul, a kind of Outward Bound for our soul. It's not about which one of us will be the survivor, for we all will survive, but it is about surviving temptation, which is what today's gospel passage is about. After Jesus is baptized, the Spirit leads him into the wilderness, where for 40 days he was tempted by the devil.
Clergy are great at that one.
And here, in the gospel story, Jesus must give up that need. We're tempted to do something immediately much of the time instead of listening and being still. The second temptation is the need for power or control, symbolized by the devil showing Jesus all the kingdoms of the world and their splendor. We love this one. We dislike being vulnerable and not being high functioning, over-achieving and looked up to.