Adam Clarke on Amos 4:5

Over a sacrifice of thanksgiving - To the senseless metal, and the unfeeling stock and stone images, from which ye never did, and never could receive any help. Proceed yet farther, and bring free-will offerings; testify superabundant gratitude to your wooden and metallic gods, to whom ye are under such immense imaginary obligations! Proclaim and publish these offerings, and set forth the perfections of the objects of your worship; and see what they can do for you, when I, Jehovah, shall send drought, and blasting, and famine, and pestilence, and the sword among you.