Jamieson, Fausset and Brown on 2 Corinthians 2:16

16. savour of death unto death ... of life unto life--an odor arising out of death (a mere announcement of a dead Christ, and a virtually lifeless Gospel, in which light unbelievers regard the Gospel message), ending (as the just and natural consequence) in death (to the unbeliever); (but to the believer) an odor arising out of life (that is, the announcement of a risen and living Saviour), ending in life (to the believer) (Mt 21:44; Lu 2:34; Joh 9:39).

who is sufficient for these things?--namely, for diffusing aright everywhere the savor of Christ, so diverse in its effects on believers and unbelievers. He here prepares the way for one purpose of his Epistle, namely, to vindicate his apostolic mission from its detractors at Corinth, who denied his sufficiency. The Greek order puts prominently foremost the momentous and difficult task assigned to him, "For these things, who is sufficient?" He answers his own question (2Co 3:5, 6), "Not that we are sufficient of ourselves, but our sufficiency is of God, who hath made us able (Greek, 'sufficient') ministers," &c.