Saint Sergius did not accept Nikon, whether because of his youth or for some other reason. Instead, he sent him to his disciple Saint Athanasius (September 12) at Serpukhov. But Saint Athanasius would not accept him right away. Only after seeing the young man’s persistence did he tonsure him into the monastic schema.
Saint Nikon struggled in prayer, studied Holy Scripture and persevered in virtue and purity. Because of his humility and the way he fulfilled each task assigned him without argument, Saint Nikon was called a “zealot of obedience.” When he reached the age of thirty, he was ordained to the priesthood. After a certain while, Saint Athanasius blessed him to go see Saint Sergius. Saint Sergius, catching sight of him, said, “It is good that you have come, my child Nikon,” and happily received him.
At first, he gave orders for Saint Nikon to serve the brethren. The disciple passed whole days in monastic matters, and his nights in prayerful conversation with God. Saint Sergius was comforted by his virtuous life. Having received a special insight concerning him, Saint Sergius bade his disciple to dwell with him in his own cell, so that he might share in spiritual attainment. He instructed him in every monastic virtue, and explained much about the essence of spiritual life. Saint Sergius assigned Saint Nikon to the duty of assisting him, but six months before his repose, he appointed his disciple as his successor. Then Saint Sergius withdrew into seclusion.
After the death of Saint Sergius (September 25, 1392), Nikon carried out his duties exactly as he was instructed by the founder of the monastery. He had the habit of attending all the monastic services, and never did he forsake common tasks, working on a equal footing with all the brethren. But the burden of being the igumen of the monastery weighed upon Saint Nikon. Recalling his quiet life in the Serpukhov Vysotsk monastery with Saint Athanasius, and later with Saint Sergius, he gave up his position and retired to his own cell.
For six years the monastery was guided by Saint Sava of Storozhevsk (December 3). In the year 1400 Saint Sava founded his own monastery near Zvenigorod, and the brethren entreated Saint Nikon to again take over its direction. He consented, but allotted himself a certain time each day for silence, so as to stand alone before God.
When reports began to spread about an invasion of the Russian land by Khan Edigei (1408), Saint Nikon zealously prayed to God to spare the monastery. In a dream the Moscow hierarchs Peter (December 21) and Alexis (February 12) together with Saint Sergius appeared to him and said that he should not grieve over the destruction of the monastery, since it would not become desolate, but would flourish all the more.
The monks left the monastery, taking with them relics, books, and consecrated vessels. When they returned, they saw that their beloved place had been reduced to ashes. But Saint Nikon did not despair, and the brethren began to restore the monastery. First of all a wooden church was built in honor of the Most Holy Trinity. It was consecrated on September 25, 1411, the anniversary of the repose of Saint Sergius.
The monastery was restored, and Saint Nikon began construction of a stone church over the grave of his spiritual Father, Saint Sergius. The work crew digging the foundations uncovered the incorrupt relics of Saint Sergius on July 5, 1422. Amidst universal rejoicing they placed the relics in a new reliquary and at the new site a wooden church was built (now the church in honor of the Descent of the Holy Spirit is at this place). Saint Nikon later built a new stone church in the Name of the Most Holy Trinity. In honor and memory of his spiritual Father, he transferred the holy relics into this newly built church.
Saint Nikon brought in the finest iconographers, Saints Andrew Rublev (July 4) and Daniel Cherny (June 13) for the adornment of the temple. Then Saint Andrew painted the Icon of the Most Holy Trinity (Hospitality of Abraham), embodying what was revealed to Saint Sergius. Saint Nikon was occupied with the construction of the Trinity church until the end of his life.
Saint Nikon’s final resting place was revealed to him in a vision before his death. He summoned the brethren and gave them instructions. After receiving the All-Pure Body of Christ and His Precious Blood, Saint Nikon gave the brethren a last blessing and said, “Go forth, my soul, with joy to the place where repose is prepared for you. Christ is calling you.”
Having made the Sign of the Cross, Saint Nikon died on November 27, 1426. He was buried near the reliquary of Saint Sergius. Under the hierarch Jonah (1448-1461), the hieromonk Pachomius the Logothete wrote the Service and Life of Saint Nikon. In the year 1547 a generally observed celebration to him was established. In the year 1548 a church named for him was built over the grave of Saint Nikon. In 1623 a new one was constructed in its place, in which the relics of Saint Nikon rest in a crypt. The 500 year anniversary of the repose of Saint Nikon was solemnly observed in 1976 at the Trinity-Sergeev Lavra.