St. Isaac (in the world, Ivan Ivanovich Antimonov) was born on May 31, 1810 in Kursk, into a pious merchant family. His parents were distinguished by their honesty, charity to the poor, and diligence in beautifying the temple. In an atmosphere of love, obedience and strict Christian order, the character of the future saint was formed. Since childhood, he was modest, kind, taciturn, and at the same time simple and witty in communication.
The thought of becoming a monk matured in his soul for a long time. Helping his father in trade, Ivan Antimonov did not abandon his desire to devote his life to God. In 1847, at the age of thirty-six, he entered the monastery of the Vvedenskaya Optina Hermitage as a novice.
His spiritual mentor was St. Macarius of Optina. Novice John worked in the apiary, bakery, and monastery refectory, sang in the choir, and bound books. He performed all the tasks with zeal and humility, strictly observing the prayer rule and the church charter. In 1854, he was tonsured a monk with the name Isaac, and in 1858 he was ordained a hieromonk.
Before his death, St. Macarius blessed Father Isaac to come under the spiritual guidance of St. Ambrose of Optina. In 1862, after the death of the abbot of the monastery, St. Moses, Father Isaac became his successor.
For more than thirty years, St. Isaac ruled the Optina desert. Churches were improved under him, a monastery hospital with a pharmacy and a church in the name of St. Hilarion the Great were built, a new hotel, a bookstore and other necessary buildings appeared. Through the abbot's care, the monastery's economy was strengthened, and gardens and vegetable gardens were developed. In the second half of the 19th century, Optina Pustyn became one of the most well-maintained monasteries in Russia.
However, the main task of the monk was the spiritual care of the brethren. As abbot, and since 1885 as archimandrite, he himself remained the obedient spiritual son of Elder Ambrose and did not undertake important tasks without his blessing. "Fathers and brothers! You need to go to the elder to clear your conscience," he often reminded the monks. Together with everyone else, the abbot stood in line to his confessor and talked with him, kneeling like a simple novice.
The last years of the monk's life were filled with illnesses and sorrows. Weakening physically, he privately took tonsure in the great schema. Before his death, the saint addressed the brethren with a final admonition: "Love God and your neighbors, love the Church of God, and in church service and prayer seek not earthly but heavenly blessings."
St. Isaac of Optina rested peacefully in the Lord on August 22 (September 4), 1894. His whole life became an example of humility, unwavering obedience, active love and fidelity to the spiritual traditions of the Optina Desert.