From St. Luke The Evangelist Catholic Church, Houston, TX:
At times even some "seasoned Catholics" get stumped by the question "What is the difference between Anointing of the Sick and Last Rites?" Many of us get confused and believe it is the same thing just a different way of naming it. Well, there is a difference and it is important for us to know these differences so that we can better understand and take full advantage of this Sacrament and this Apostolic Blessing (Last Rites).
Anointing of the Sick
Most of us usually think of asking for this anointing only when we are nearing death through sickness or old age. However, if this is the case, we would be missing out on the opportunity for God to heal and help us at times when we might need Him the most - when we are having surgery, dealing with a physical, mental, emotional, or even spiritual affliction. It is during these difficult times that we need the Holy Spirit's gifts of strength, faith, peace, and courage. It is during these times, as well, that we should seek to receive this God-given sacrament.
How can we decide if we should ask to be anointed? Well, a good or reasonably sure judgment, without an uneasy feeling about the rightness of what one is doing or going to do, is sufficient for deciding on the seriousness of an illness. For example:
• A sick person may be anointed before surgery, whether or not a serious illness is a 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. And if you are still unsure, when in doubt...ask a priest!
The anointing of the sick is administered, by a bishop or priest, to bring spiritual and even physical strength during an illness. This sacrament, unlike some of our other sacraments, can be administered more than once, especially if a person has a chronic illness.
"The special grace of the sacrament of the Anointing of the Sick has as its effects:
A. The uniting of the sick person to the passion of Christ, for his own good and that of the whole Church
B. The strengthening, peace, and courage to endure in a Christian manner the sufferings of illness or old age
C. The forgiveness of sins, if the sick person was not able to obtain it through the sacrament of penance the restoration of health, if it is conducive to the salvation of his soul the preparation for passing over to eternal life" (CCC 1532).