Alexander Grenkov, the future father of Ambrose, was born in November 1812, into the spiritual family of the village of Bolshiye Lipovitsy, Tambov Diocese. After graduating from the Theological School, he then successfully completed a course at the Theological Seminary. However, he did not go to the Theological Academy or to the priesthood. For some time he was a home teacher in a landowner family, and then a teacher at the Lipetsk Theological School. Possessing a lively and cheerful character, kindness and wit, Alexander Mikhailovich was very loved by his comrades and colleagues. In the last class of the Seminary, he had to endure a dangerous illness, and made a vow to become a monk if he recovered.
Upon recovery, he did not forget his vow, but for several years he postponed its fulfillment, «», as he put it. However, his conscience haunted him. And the more time passed, the more painful the reproaches of conscience became. Periods of carefree fun and carelessness were replaced by periods of acute melancholy and sadness, intense prayer and tears. Once, already in Lipetsk, walking in the neighboring forest, he, standing on the bank of a stream, clearly heard the words in his murmur: «Praise God, love God...».
At home, secluded from curious gaze, he fervently prayed to the Mother of God to enlighten his mind and direct his will. In general, he did not have persistent will and already in old age he told his spiritual children: «You must obey me from the first word. I am a compliant — person. If you argue with me, I may give in to you, but it won't benefit you». Exhausted from his indecisiveness, Alexander Mikhailovich went for advice to the famous ascetic Hilarion, who lived in that area. «Go to Optina, — the old man told him, — and you will be experienced». Grenkov obeyed. In the autumn of 1839, he arrived in Optina Pustyn, where he was affectionately received by Elder Leo.
Soon he took monastic vows and was named Ambrose, in memory of St. Mediolanus, then was ordained a hierodeacon and, later, a hieromonk. When Father Macarius began his publishing business, Father Ambrose, who graduated from the seminary and was familiar with ancient and new languages (he knew five languages), was one of his closest assistants. Soon after his ordination he fell ill. The disease was so severe and long lasting that it permanently damaged the health of Ambrose's father and almost confined him to bed. Due to his painful condition, until his death he could not celebrate liturgies or participate in long monastic services.
The Monk Ambrose died on October 23, 1891 in the Shamorda monastery and was buried in the Optina Hermitage next to the grave of the Monk Elder Macarius. After his death, Elder Ambrose appeared to many people in different parts of Russia, healing the sick, helping the suffering. The holiness of the life of Elder Ambrose is revealed in his active love for his neighbors, and the Orthodox people have always responded to him with deep veneration. In 1988, at the Local Council of the Russian Orthodox Church, St. Ambrose was canonized as a saint of God. His discovered honest relics (in 1998) rest in the Vvedensky Cathedral of Optina Pustyn.