"In the Church's Sacrament of Anointing of the Sick, through the ministry of the priest, it is Jesus who touches the sick to heal them from sin – and sometimes even from physical ailment. His cures were signs of the arrival of the Kingdom of God. The core message of his healing tells us of his plan to conquer sin and death by his dying and rising.

The Rite of Anointing tells us there is no need to wait until a person is at the point of death to receive the Sacrament. A careful judgment about the serious nature of the illness is sufficient.

When the Sacrament of Anointing of the Sick is given, the hoped-for effect is that, if it be God's will, the person be physically healed of illness. But even if there is no physical healing, the primary effect of the Sacrament is a spiritual healing by which the sick person receives the Holy Spirit's gift of peace and courage to deal with the difficulties that accompany serious illness or the frailty of old age."

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From Pastoral Care of the Sick: Rites of Anointing and Viaticum, Recipients of the Anointing of the Sick #8-13.

“Great care and concern should be taken to see that those of the faithful whose health is seriously impaired by sickness or old age receive this sacrament.  The sacrament may be repeated if the sick person recovers after being anointed and then again falls ill or if during the same illness the person’s condition becomes more serious.  A sick person may be anointed before surgery whenever a serious illness is the reason for the surgery.  Elderly people may be anointed if they have become notably weakened even though no serious illness is present.  Sick children may be anointed if they have sufficient use of reason to be strengthened by this sacrament.”

UNITED STATES CATHOLIC CATECHISM FOR ADULTS

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