The purpose of the command was to test faith, even more than to test whether earthly love or heavenly obedience were the stronger. There is a beautiful and instructive climax in the designations of Isaac in verse 2, where four times he is referred to, 'thy son, thine only son,' in whom all the hopes of fulfilment of the divine promise were concentrated, so that, if this fruit from the aged tree were cut off, no other could ever grow; 'whom thou lovest,'--there the sharp point pierces the father's heart; 'even Isaac,' in which name all the ties that knit him to Abraham are gathered up. Each word heightens the greatness of the sacrifice demanded, and is a fresh thrust of the dagger into Abraham's very life. Each suggests a reason for not slaying Isaac, which sense might plead. God does not hide the painfulness of surrender from us. The more precious the treasure is, the more are we bound to lay it on the altar. But it was Abraham's faith even more than his love that was tested. The Epistle to the Hebrews lays hold on this as the main element in the trial, that he who 'had received the promises' was called to do what seemed to blast all hope of their being fulfilled. What a cruel position to have God's command and God's promise apparently in diametrical opposition! But faith loosened even that seemingly inextricable tangle of contradiction, and felt that to obey was for man, and to keep His promise was for God. If we do our duty, He will see to the consequences. 'Tis mine to obey; 'tis His to provide.' Nothing in literature is more tenderly touched or more truly imagined than that long, torturing journey--Abraham silent, Isaac silently wondering, the servants silently following. And, like a flash, at last 'the place' was seen afar off. How calmly Abraham speaks to the two followers, mastering his heart's throbbing even then! 'We will worship, and come again to you'--was that a 'pious fraud' or did it not rather indicate that a ray of hope, like pale light from a shrouded sun, shone for him? He 'accounted that God was able to raise him up even from the dead.' Somehow, he knew not how, Isaac slain was still to live and inherit the promises. Anything was possible, but that God's word should fail was impossible. That picture of the father and son alone, the one bearing the wood, the other the fire and the knife, exchanging no word but once, when the innocent wonder of Isaac's question must have shaken Abraham's steadfastness, and made it hard for him to steady his voice to answer, touches the deepest springs of pity and pathetic sublimity. But the answer is in the same spirit as that to the servants, and indicates the same hope. 'God will provide Himself a lamb, my son.' He does not know definitely what he expects; he is ready to slay Isaac, but his faith is not quenched, though the end seems so inevitable and near. Faith was never more sharply tested, and never more triumphantly stood the test.