When about twenty years of age he entered the monastery at Citeaux with five of his brothers. His genius might have secured ecclesiastical preferment, but he chose to dig ditches, plant fields and govern a monastery. He entered the cloister at Citeaux because the monks were few and poor, and when it became crowded because of his fame, and its rule became lax because of the crowds, he left the cloister to found a home of his own. The abbot selected twelve monks, following the number of apostles, and at their head placed young Bernard. He led the twelve to the valley of Wormwood, and there, in a cheerless forest, he established the monastery of Clairvaux, or Clear Valley. His rule was fiercely severe because he himself loved hardships and rough fare. "It in no way befits religion," he writes, "to seek remedies for the body, nor is it good for health either. You may now and then take some cheap herb,--such as poor men may,--and this is done sometimes. But to buy drugs, to hunt up doctors, to take doses, is unbecoming to religion and hostile to purity." His success in winning men to the monastic life was almost phenomenal. It was said that "mothers hid their sons, wives their husbands, and companions their friends, lest they be persuaded by his eloquent message to enter the cloister." "He was avoided like a plague," says one.