The brahmacari is educated in that way. Up to twenty-five years he cannot see a young woman. He cannot see even. This is brahmacari. He cannot see. Then he is trained up in that way, that he may continue a brahmacari life. Naisthika-brahmacari. But if he's unable, then he's allowed to marry. That is called grhastha life, householder life. Because between twenty-five years to fifty years, this is the youthful time, so his lusty desires are very strong. One who is not able to control… Not for all. There are many naisthika-brahmacari. Naisthika-brahmacari — throughout the life, celibacy. But that is not possible in this age, neither it is possible to become a brahmacari. The time is changed, this age. Therefore you can control your lusty desire by Krsna consciousness. Otherwise it is not possible.
From Srila Prabhupada's lecture on Bhagavad-gita 16.10 — February 6, 1975, Honolulu