The specific practices of Ablution in Christianity are generally concerned with either ritual purification, or symbolism of humility. Christian ablution may therefore refer to the practice of removing sins, diseases or earthly defilements through the use of ritual washing, or the practice of using ritual washing as one part of a ceremony to remove sin or disease.
According to the Gospel of Matthew, Pontius Pilate declared himself innocent of the blood of Jesus by washing his hands (). This act of Pilate may not, however, have been borrowed from the custom of the Jews. The same practice was common among the Greeks and Romans.
According to Christian tradition, the Pharisees carried the practice of ablution to great excess (). The Gospel of Mark refers to their ceremonial ablutions (): For the Pharisees...wash their hands "oft"; or, more accurately, "with the fist" (R.V., "diligently"); or, as Theophylact of Bulgaria explains it, "up to the elbow," referring to the actual word used in the Greek New Testament, pygmē, which refers to the arm from the elbow to the tips of the fingers. (Compare also ; ; ; ). (See Washing.)
In the Book of Acts, Paul and other men performed ablution before entering the Temple in Jerusalem: Then Paul took the men, and the next day purifying himself with them entered into the temple, to signify the accomplishment of the days of purification, until that an offering should be offered for every one of them ().
The ablutions will normally be performed by the deacon, but if no deacon is serving the priest will do them. After the Litany of Thanksgiving that follows Communion, the deacon will come into the sanctuary and kneel, placing his forehead on the Holy Table (Altar) and the priest will bless him to consume the Gifts, which is done at the Prothesis (Table of Oblation). First, using the liturgical spoon he will consume all of the Body and Blood of Christ which remain in the chalice. Then he will pour hot water on the diskos (paten), which is then poured into the chalice and consumed (this is to consume any particles that may remain on the diskos). Next the liturgical spear, spoon and chalice will be rinsed first with wine and then with hot water, which are then consumed. All of the sacred vessels are then wiped dry with a towel, wrapped in their cloth coverings and put away.
Because the ablutions necessarily require consuming the Holy Mysteries (the Body and Blood of Christ), a priest or deacon may only perform them after having fully prepared himself through fasting and the lengthy Preparation for Holy Communion.
When a priest must take Holy Communion to the sick or homebound, if he has not prepared himself to receive the Holy Mysteries, he may ablute the chalice by pouring water into it and asking the one to whom he brought the Sacrament (or a Baptized child who because of their youth is not obliged to prepare for Communion) to consume the ablution.
If the Reserved Mysteries should become moldy, they must still be consumed in the same manner as the ablutions after Liturgy (normally, a fair amount of wine would be poured over them before consuming them, in order to soften and disinfect them). They should not be burned or buried. To prevent this, when the Mysteries are to be reserved for the sick, they should be thoroughly dried before being placed in the Tabernacle.
The newly-illumined (newly-baptized person) is brought back to the church by his Godparents for the ablutions. The priest stands him in the center of the church, in front of the Holy Doors, facing east. He loosens the belt of the baptismal robe and prays for him, that God may preserve the newly-illumined in purity and illumine him by grace. He then dips a sponge in water and sprinkles him in the sign of the cross saying: "Thou art justified. Thou art illumined. Thou art sanctified. Thou art washed: in the name of the Father, and of the Son, and of the Holy Spirit. Amen." Then, as he says the next prayer, he washes each of the places where he had been anointed with Chrism. Next he performs the Tonsure, symbolic of the life of self-sacrifice a Christian must lead.
Many Christian churches practice a ceremony of the Washing of Feet, following the example of Jesus in the Gospel (). Some interpret this as an ordinance which the church is obliged to keep as a commandment. Others interpret it as an example that all should follow. Most denominations that practice the rite will perform it on Maundy Thursday. Often in these services, the bishop will wash the feet of the clergy, and in monasteries the Abbot will wash the feet of the brethren.
St. Benedict of Nursia lays out in his Rule that the feet of visitors to the monastery should be washed, and also that those who are assigned to serve in the kitchen that week should wash the feet of all the brethren.
When an Orthodox priest or bishop dies, these ablutions and vesting are performed by the clergy, saying the same prayers for each vestment that are said when the departed bishop or priest vested for the Divine Liturgy. After the body of a Bishop is washed and vested, he is seated in a chair and the Dikirion and Trikirion are placed in his hands for the final time.
When an Orthodox monk dies, his body is washed and clothed in his monastic habit by brethren of his monastery. Two significant differences are that when his mantle is placed on him, its hem is torn to form bands, with which his body is bound (like Lazarus in the tomb), and his klobuk is placed on his head backwards, so that the monastic veil covers his face (to show that he had already died to the world, even before his physical death). When an Orthodox nun dies, the sisterhood of her convent performs the same ministrations for her as are done for monks.