Corporal need occurs either during this life or afterwards. If it occurs during this life, it is either a common need in respect of things needed by all, or it is a special need occurring through some accident supervening. On the first case, the need is either internal or external. Internal need is twofold: one which is relieved by solid food, viz. hunger, in respect of which we have "to feed the hungry"; while the other is relieved by liquid food, viz. thirst, and in respect of this we have "to give drink to the thirsty." The common need with regard to external help is twofold; one in respect of clothing, and as to this we have "to clothe the naked": while the other is in respect of a dwelling place, and as to this we have "to harbor the harborless." Again if the need be special, it is either the result of an internal cause, like sickness, and then we have "to visit the sick," or it results from an external cause, and then we have "to ransom the captive." After this life we give "burial to the dead."
St. Thomas Aquinas, ST 2-2.32.2
