Therefore they sacrifice unto their net, and burn incense unto their drag; because by them their portion is fat, and their meat plenteous.
Therefore they sacrifice unto their net - i:e., their arms, power, and military skill, wherewith they gained their victories; instead of to God. Compare Habakkuk 1:11, Maurer's intepretation, 'as one to whom his power is his god.' They idolize themselves for their own cleverness and might (Deuteronomy 8:17; Isaiah 10:13; Isaiah 37:24-25). Because by them - by their net and drag net.
Their portion is fat - image from a banquet: the pray which they have gotten.