Genesis 17:15-18:15: Summary: The disclosure of God's covenant with Abraham continues. Told that it will be fulfilled in Isaac, through Sarah, Abraham, supposing it impossible, laughs. Surely the Almighty will make use of what we've already illicitly provided. No, God says. The son of promise will not be produced by people in their slavery to sin, not by nature. The son of promise will be a free gift of God to the world. When Abraham wants to run back to Genesis 16, God insists on His way forward. In faith, Abraham sets the sign of the covenant upon himself and all in his house, slave or free. The Lord then appears in the vision of three. Abraham rushes to greet them and to enlist Sarah and a young man of the house to show the Lord their hospitality. Abraham pleads the grace of God's ministry among them. The Lord in the three asks Sarah's whereabouts. He reiterates that in the year Sarah will bear Isaac, with whom God will establish the covenant of redemption. Sarah, listening to God speak, laughs at what God says. God reproves Abraham for Sarah's unbelief. Sarah tries to hide the fact of it, but nothing is hidden from the Lord. 'No, but you did laugh,' He says. God will have the last laugh and, in the meantime, believers are to feed faith on these words: Is anything too hard for the Lord? Sermon Outline: A faith feeding on God will trust, and not laugh at, the means of God. (17:15-27) A faith feeding on God will pray on, and not laugh at, a meeting with God. (18:1-8) A faith feeding on God will minister, and not laugh at, the might of God. (18:9-15)