4:17-24 Sisera's chariots had been his pride and his confidence. Thus are those disappointed who rest on the creature; like a broken reed, it not only breaks under them, but pierces them with many sorrows. The idol may quickly become a burden, Isa 46:1; what we were sick for, God can make us sick of. It is probable that Jael really intended kindness to Sisera; but by a Divine impulse she was afterwards led to consider him as the determined enemy of the Lord and of his people, and to destroy him. All our connexions with God's enemies must be broken off, if we would have the Lord for our God, and his people for our people. He that had thought to have destroyed Israel with his many iron chariots, is himself destroyed with one iron nail. Thus the weak things of the world confound the mighty. The Israelites would have prevented much mischief, if they had sooner destroyed the Canaanites, as God commanded and enabled them: but better be wise late, and buy wisdom by experience, than never be wise.
17, 18. Sisera fled … to the tent of Jael—According to the usages of nomadic people, the duty of receiving the stranger in the sheik's absence devolves on his wife, and the moment the stranger is admitted into his tent, his claim to be defended or concealed from his pursuers is established.