Jamieson, Fausset and Brown on 1 John 3:17

17. this world's good--literally, "livelihood" or substance. If we ought to lay down our lives for the brethren (1Jo 3:16), how much more ought we not to withhold our substance?

seeth--not merely casually, but deliberately contemplates as a spectator; Greek, "beholds."

shutteth up his bowels of compassion--which had been momentarily opened by the spectacle of his brother's need. The "bowels" mean the heart, the seat of compassion.

how--How is it possible that "the love of (that is, 'to') God dwelleth (Greek, 'abideth') in him?" Our superfluities should yield to the necessities; our comforts, and even our necessaries in some measure, should yield to the extreme wants of our brethren. "Faith gives Christ to me; love flowing from faith gives me to my neighbor."