Plants begin as a seed and the seed reaches its completion when it produces the seed for the next generation.
Man likewise goes through a process of growth.
Like plants and animals, human beings grow naturally to their completion. As we can see from the dilemma of teenage pregnancies, it is not enough that a human can reproduce. There is another responsibility involved with human growth, and that is completion of their spirit. This completion of man's spirit involves a sincere effort on man's part. Originally, man was meant to grow in the true love of True Parents, directly receiving God's love and growing in an environment of support, encouragement, sensitivity and love.