"Lay down necks," i.e. risked their lives (Romans 16:4). Psalm 18:40, "Thou hast given ... necks of enemies," i.e. made them turn their backs in flight before me (Keil); so Exodus 23:27, or enabled me to put my foot on their necks, subjecting them utterly to me; as Joshua 10:24; Joshua 11:8; Joshua 11:12; Psalm 110:5. Isaiah 8:8, "he shall overflow, he shall reach even to the neck": when the waters reach the neck a man is near drowning; Sennacherib's overflowing hosts reached so far, but Jerusalem the head was not overflowed (Isaiah 30:28; Habakkuk 3:13). The "stiff neck" is an image from oxen unpliant and casting the "yoke" off the neck (Acts 7:51; Matthew 11:29). Contrast the yoke men must wear who reject Christ's easy yoke (Deuteronomy 28:48).