Peter Adamovich Nizhnik was born on January 16, 1895 in the village of Rechitza, of the Grodenenskaya guberniya, Pruzhansky uezd, Gorodechnyansky volost' of what is now Belarus, to a large, poor family. Peter's parents wanted him to marry. However, Peter did not want to marry at all, but offered his parents to go to America to work and, as then was commonly done, send money back to them. Peter's mother, having seen what happened to other emigrants who went to America, get rich, and then become atheists, begged her son with tears to "not lose God".
Taking his mother's comments to heart, Peter traveled to the United States in 1913 and set to work in a sugar factory near Chicago, Illinois. His job required him to work on holidays and Sundays, making a Christian life difficult. He often silently prayed to God, "Show me the way, O Lord, and I shall follow." Peter suffered many temptations, but was strengthened and learned to reject temporal contentment.
With the start of World War I in Europe In 1914, his homeland was invaded resulting in the destruction of towns and villages, including Rechitza. His parents and relatives were scattered throughout Russia. Only sad news from home reached Peter over next several years, culminating in the disaster to his country with the Bolshevik revolution in late 1917. Now, considering his future and fighting external temptations, Peter, remembered the inner voice of his guardian angel in response to his prayer and "strengthened me against the devil's enticements, and helped me dispense with dreams of establishing myself in temporary worldly contentment."
The October Revolution of 1917 in Russia was a turning point in Peter's life. On April 18, 1918, Peter, now 23 years old, entered St. Tikhon's Monastery in South Canaan, Pennsylvania as a novice. In 1920, he was tonsured a monk with the name Panteleimon. Soon after, Panteleimon was ordained a hierodeacon. On April 10, 1921, he was ordained a hieromonk.
Through the years at St. Tikhon's Monastery, Fr. Panteleimon struggled with gaining a genuine monastic life. During these years Ivan Andreevich Kolos, a choir director and psalm-reader at a nearby parish, came to the monastery with a similar urning for a real monastic life. The two decided to purchase some land. Fr. Panteleimon then left the monastery to work at the Sikorsky Manufacturing Company in New York. In 1928, Fr. Panteleimon and Ivan Kolos purchased a parcel of land in upstate New York that became Holy Trinity Monastery. Fr. Panteleimon remained working at Sikorsky until they were able to pay off the cost of the land purchase in 1930.
With the acquisition of land for the monastery, Fr. Panteleimon and Ivan Kolos were joined by Fr. Jacob from St. Tikhon's Monastery. In 1930, Holy Trinity Monastery was established with the blessing of Abp. Apollinarius of North America. with five brethren, including Fr. Panteleimon.
On the day of Pentecost in 1935, the consecration of the church and monastery was held, led by Bp. Vitaly (Maximenko). At the end of the Liturgy, smoke was seen at the second floor of the monastic house. In a few hours, everything had burnt to the ground. With the help of Hieromonk Ilya (Gavriliuk), a good carpenter, the house was rebuilt later that year. At the time Bp. Vitaly also tonsured Ivan Kolos a monk with the name Joseph. Under Archim. Panteleimon leadership, during the following decade construction continued at the monastery as it grew toward the community it is today.
Archim. Panteleimon retired as abbot at Holy Trinity Monastery in 1946 and reposed in 1984.