3:5-11 It is our duty to mortify our members which incline to the things of the world. Mortify them, kill them, suppress them, as weeds or vermin which spread and destroy all about them. Continual opposition must be made to all corrupt workings, and no provision made for carnal indulgences. Occasions of sin must be avoided: the lusts of the flesh, and the love of the world; and covetousness, which is idolatry; love of present good, and of outward enjoyments. It is necessary to mortify sins, because if we do not kill them, they will kill us. The gospel changes the higher as well as the lower powers of the soul, and supports the rule of right reason and conscience, over appetite and passion. There is now no difference from country, or conditions and circumstances of life. It is the duty of every one to be holy, because Christ is a Christian's All, his only Lord and Saviour, and all his hope and happiness.
5. Mortify—Greek, "make a corpse of"; "make dead"; "put to death."
therefore—(See on Col 3:3). Follow out to its necessary consequence the fact of your having once for all died with Christ spiritually at your regeneration, by daily "deadening your members," of which united "the body of the sins of the flesh" consists (compare Col 2:11). "The members" to be mortified are the fleshly instruments of lust, in so far as the members of the body are abused to such purposes. Habitually repress and do violence to corrupt desires of which the members are the instruments (compare Ro 6:19; 8:13; Ga 5:24, 25).
upon the earth—where they find their support [Bengel] (Compare Col 3:2, "things on earth"). See Eph 5:3, 4.
inordinate affection—"lustful passion."
evil concupiscence—more general than the last [Alford], the disorder of the external senses; "lustful passion," lust within [Bengel].
covetousness—marked off by the Greek article as forming a whole genus by itself, distinct from the genus containing the various species just enumerated. It implies a self-idolizing, grasping spirit; far worse than another Greek term translated "the love of money" (1Ti 6:10).
which is—that is, inasmuch as it is "idolatry." Compare Note, see on Eph 4:19, on its connection with sins of impurity. Self and mammon are deified in the heart instead of God (Mt 6:24; see on Eph 5:5).