Father Adrien had taken the vows of eternal silence, prayer and, of course, celibacy, when he entered the Trappist Monastry of Notre Dame d'Afrique in Algeria. One day, he chopped down a tree that blocked a part of the Monastery wall, but as it fell it knocked a young girl senseless. As Father Adrien bathes her face she regains consciousness and in a mischievous mood embraces him. The embrace was seen by another monk but the Monastic discipline imposed is as nothing compared to the torturing penances of mind and body which the contrite Father Adrien has imposed upon himself. In the end it is all too much for poor Father Adrien and he abandons his vows and escapes into the desert, resuming his secular name Androvsky. On the way to the oasis of Beni-Mora he encounters Domini Enfilden who has been brought up as a Catholic. Androvsky rescues Domini from a rioting crowd and she finds herself deeply attracted to him.

Father Adrien, by taking the vow of silence, constant prayer, and chastity, gains entrance to the Trappist Monastery of Notre Dame d'Afrique in Algeria. While clearing a tree from the monastery wall, he accidentally knocks a young girl unconscious, and on reviving she intrigues him into an embrace; his sin is reported by an onlooker and he is forced to undergo penance; but the beauty of woman and the outside world entice him to renounce his vows and escape into the desert, resuming his secular name, Androvsky. En route to the oasis of Beni-Mora, he encounters Domini Enfilden, a deeply religious girl, and rescues her from a Bedouin riot. At a party in the gardens of Count Anteoni, she notes his fear of the cross and of priests, and he breaks away, frightened by a sand-diviner. In face of warnings, Domini marries Androvsky, and they go into the desert; Anteoni realizes his true identity but agrees to keep it secret. During a sandstorm, Androvsky confesses to having broken his vows and returns to the monastery to do penance. Years later, Domini sings to their son a song of freed Bedouin slaves: "Only God and I know what is in my heart."