The feast of the Baptism of the Lord is a commemoration of the evangelical event when Christ came to the banks of the Jordan River and was baptized by the prophet John the Baptist. John preached among the Jews the baptism of repentance for the forgiveness of sins, coming to the deserted bank of the Jordan to John the Baptist, people confessed their wrongs and symbolically washed them off themselves in river water. When the sinless Christ came to John and also expressed a desire to be baptized, he was amazed: I need to be baptized by You, and do You come to me? (Matt. 3:14) But I heard in response: This is how we must fulfill all righteousness, that is, God's will. Christ, as a Man, had to fulfill all the ordinances of the Jewish law in order to overcome it and give His new law of grace. John had no choice but to allow Jesus to be baptized.

The feast of the Baptism of the Lord is a commemoration of the evangelical event when Christ came to the banks of the Jordan River and was baptized by the prophet John the Baptist (Matthew 3:13-17; Mark 1:9-11; Luke 3:21-22). In the original Greek text of the Gospel, baptism is designated by the word βάπτισμα, which literally means "immersion in water." John preached among the Jews the baptism of repentance for the remission of sins (Mark 1:4): when people came to the deserted bank of the Jordan to John the Baptist, they confessed their iniquities and symbolically washed them off in river water. When the sinless Christ came to John and also expressed a desire to be baptized, he was amazed: I need to be baptized by You, and do You come to me? (Matthew 3:14) But he heard in reply: This is how we must fulfill all righteousness (Matthew 3:15), that is, God's will. Christ, as a Man, had to fulfill all the ordinances of the Jewish law in order to overcome it and give His new law of grace. John had no choice but to allow Jesus to be baptized.
Immediately after this, the Holy Spirit descended on Christ in the form of a dove, and a voice thundered from heaven: "You are my beloved Son; I am well pleased with you" (Luke 3:22). It was God the Father who testified that Jesus is not only the Son of Man, but also the Son of God. Thus, in the event of Epiphany, all the Persons of the Holy Trinity appeared in a visible way for the first time, therefore the holiday received a second name — Epiphany.
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Christ did not need to wash away His sins — He did not have them. But He came into the world in order to take responsibility for the filth of others, for the sins of all people who lived in the world before Him, during His earthly life and after Him, and to atone for them by suffering on the Cross. Entering the waters of the Jordan, the Savior took the very first step on this path — symbolically took upon Himself human sins, explains St. John Chrysostom.
By descending into the waters of the Jordan, Christ rededicated the aquatic nature, and through it, the entire created nature. Once upon a time, the fall of Adam and Eve changed the whole world: not only man, but also nature, with which he is closely connected, bore the mark of sin and death — the consequences of falling away from God. But Christ, having plunged into the Jordan, renewed the waters, and with them the whole created world, freeing them from filth and corruption. It is no coincidence that the main Christian sacrament, Baptism, is performed with "water and the Spirit": consecrated water receives the grace of the Holy Spirit, and by immersing in it, the believer is just as spiritually renewed and born as a Christian. This is the difference between the sacrament of Baptism, established by Christ (see John 3:5), and the baptism of John, which led a person to repentance, but did not imply his spiritual rebirth.
The consecration of water is the most striking feature of the holiday. The water consecrated the day before, on the Eve (otherwise called Epiphany Eve) and on the day of Theophany itself, the Church calls agiasm, that is, the great shrine. It has been preserved for months and even years, and has the property of healing people from diseases and strengthening them spiritually, precisely because, through the prayer of the Church, it acquires the properties of a renewed universe, freed from the consequences of human sin. Of course, the miraculous properties of epiphany water manifest themselves only if a person has faith.
In the old days in Russia, any hole in the ice of a river or lake, created for the purpose of baptismal consecration of water, was called the Jordan.
 Consecration of water for Baptism. Kirillo-Belozersky Monastery. Photo by Vladimir Yeshtokin
The white color of the priests' vestments on the feast of Epiphany (as well as Christmas) is explained by the fact that it was the custom of the early Church to baptize new converts on these days.
History
The celebration of the Epiphany began during the lifetime of the apostles. At that time, these were long celebrations dedicated to the appearance of God into the world, both His Nativity and Baptism (which was, in fact, the first appearance of Christ in a large gathering of people). In the fourth century, these holidays were divided, and the time between them eventually began to be called holy, or Yuletide.