"One of the seven sacraments, also known as the 'sacrament of the dying,' administered by a priest to a baptized person who begins to be in danger of death because of illness or old age, through prayer and the anointing of the body with the oil of the sick. The proper effects of the sacrament include a special grace of dealing and comfort to the Christian who is suffering the infirmities of serious illness or old age, and the forgiving of the person's sins (1499, 1520, 1523, 1526-1532)." Catechism of the Catholic Church
"Is anyone among you suffering? He should pray. Is anyone in good spirits? He should sing praise. Is anyone among you sick? He should summon the presbyters of the church, and they should pray over him and anoint [him] with oil in the name of the Lord, and the prayer of faith will save the sick person, and the Lord will raise him up. If he has committed any sins, he will be fogiven." James 5:13-15