Question: George Mueller tells how God uses trials to increase our faith. But Abraham's life (for example) proves that notion wrong. Otherwise, God would be a child abuser!
Response: The command to offer Isaac was not a "trial" to help Abraham's faith grow; it was a test of his obedience (Gn 22:1), and he passed it well, confident that God would raise Isaac from the dead (Heb:11:17-19). Isaac's being bound on the altar was not child abuse. He was carrying the wood, so was more than a child, strong enough to have resisted and at least to have run away. There is no record that he attempted this, nor of any struggle. Isaac's willing submission to his father is a beautiful picture of Christ's willing submission to His Father's will, in allowing Himself to be mocked, scourged, beaten, and nailed to that cross—and then to bear the wrath of God in punishment for the sins of the world. Abraham seemed to have some comprehension of that great coming sacrifice. Isaac asked, "Where is the lamb for a burnt-offering?" Abraham replied, "God will provide himself a lamb for a burnt-offering." (Gn 22:7, 8). What else could Christ have referred to than this statement by Abraham when He told the Jews, "Your father Abraham rejoiced to see my day: and he saw it, and was glad" (Jn:8:56)?