Jamieson, Fausset and Brown on 1 Corinthians 1:18

18. preaching, &c.--literally, "the word," or speech as to the cross; in contrast to the "wisdom of words" (so called), 1Co 1:17.

them that perish--rather, "them that are perishing," namely, by preferring human "wisdom of words" to the doctrine of the "cross of Christ." It is not the final state that is referred to; but, "them that are in the way of perishing." So also in 2Co 2:15, 16.

us which are saved--In the Greek the collocation is more modest, "to them that are being saved (that are in the way of salvation) as," that is, to which class we belong.

power of God--which includes in it that it is the wisdom of God" (1Co 1:24). God's powerful instrument of salvation; the highest exhibition of God's power (Ro 1:16). What seems to the world "weakness" in God's plan of salvation (1Co 1:25), and in its mode of delivery by His apostle (1Co 2:3) is really His mighty "power." What seems "foolishness" because wanting man's "wisdom of words" (1Co 1:17), is really the highest "wisdom of God" (1Co 1:24).