Becoming A Butterfly
The essential point is that living beings do not undergo sudden, complete transformations. The caterpillar does not become a butterfly in a single act but as a result of a gradual process, governed by certain laws. Within the process there appears to be a series of jumps between distinct stages, and these the baal teshuvah must make from time to time. But these transitions, too, are neither as quick nor as sharp as they appear. Sudden entry into the world of Jewish religious life is a rare phenomenon for the simple reason that these changes are highly complex. The acceptance of Judaism is not a matter of one-time affirmations or moments of revelation. Such transitory experiences can be important as turning points, but in Judaism they can only serve as the starting point of a very long journey.
(Rabbi Adin Steinsaltz)