Exodus 7:19
And the Lord spake unto Moses, Say unto Aaron, Take thy rod, and stretch out thine hand upon the waters of Egypt, upon their streams, upon their rivers, and upon their ponds, and upon all their pools of water, that they may become blood; and that there may be blood throughout all the land of Egypt, both in vessels of wood, and in vessels of stone.
Cross-references
Exodus 8:5 repeats the same command formula for the frog plague: Aaron stretches staff over waters. This shows the consistent pattern of divine instruction through Moses and Aaron.
Exodus 8:6 records the execution of the frog plague, mirroring the blood plague execution. Both involve Aaron stretching his hand over Egypt's waters.
In Exodus 8:16, the command shifts to striking dust for gnats, but the action 'stretch out your staff' echoes the first plague. A variation on the same divine pattern.
Exodus 9:22 commands Moses to stretch his hand toward the sky for hail. Though the target changes, the gesture of power over creation remains parallel.
Exodus 9:23 shows Moses executing the hail plague, stretching his staff toward the sky. A direct parallel to Aaron's action in the first plague.
Exodus 10:12 commands Moses to stretch his hand over Egypt for locusts, continuing the pattern of plague initiation through physical gesture.
Exodus 10:21 commands Moses to stretch his hand toward the sky for darkness, another plague initiated by the same symbolic action.
Exodus 14:21 records Moses stretching his hand over the sea to part it. This action echoes the plague initiations but now brings deliverance.
Exodus 14:26 commands Moses to stretch his hand over the sea again to close it on the Egyptians. A bookend to the pattern of hand-stretching miracles.
Exodus 1:22 has Pharaoh order Hebrew babies thrown into the Nile; here the same Nile becomes blood, a divine judgment on that cruelty.
Exodus 4:9 is where God first commands turning Nile water to blood as a sign; this verse carries out that command.
Exodus 14:16 has Moses stretch his staff over the sea to part it; here Aaron stretches his staff over waters to turn them to blood.
Exodus 17:5 uses the staff to strike a rock and bring water; here the staff turns water to blood — one gives life, one brings judgment.
Exodus 4:17 tells Moses to take his staff for performing signs; here Aaron uses that staff to bring the plague.
Exodus 9:33 shows Moses spreading his hands in prayer to stop the hail. Different from plague initiation—now a gesture of intercession, not judgment.
Isaiah 11:15 also speaks of God's power over the Nile, but for deliverance rather than judgment.