Our eyes do yet fail [in looking] for our vain help: In our watching we have watched for a nation that could not save.
that is, We have persevered, and though many trials may have wearied us, yet we have been constant in our hope in God. So now the Prophet says, that the eyes of the people had failed; but he adds, for a vain help, or a help of vanity, by which term he designates the Egyptians: and there is an implied contrast between empty and fallacious help and the help of God, which the people rejected when they preferred the Egyptians. Our eyes, he says, failed, that is, we were unwearied in hoping vainly, for we always thought that the Egyptians would be a sufficient, defense to us. This is one thing. 