Exodus 15:25
And he cried unto the Lord; and the Lord shewed him a tree, which when he had cast into the waters, the waters were made sweet: there he made for them a statute and an ordinance, and there he proved them,
Cross-reference
Exodus 16:4 introduces the manna test — directly following the testing at Marah, both testing obedience.
Exodus 17:4 has Moses crying to the Lord about the people's threat to stone him, another crisis cry parallel to this one.
Exodus 14:10 shows the people crying out to the Lord in fear at the Red Sea, similar to Moses' cry here but with different petitioners.
Deuteronomy 8:2 recalls the wilderness testing that began at Marah — a direct retrospective reference.
In 2 Kings 2:21, Elisha heals bad water by throwing salt — a direct parallel to Moses' tree making bitter water sweet.
Psalm 99:6 explicitly recalls Moses calling on the Lord and being answered, directly referencing the pattern seen here.
In 1 Corinthians 1:18, the cross (wood) is the power of God — the tree in Exodus typifies Christ's cross transforming bitterness to salvation.
In 2 Kings 6:6, Elisha parallels Moses by using wood to miraculously alter water's properties, demonstrating God's power over nature.
In 2 Kings 4:41, Elisha purifies poisonous stew with flour — a similar miracle of adding an object to neutralize harm.
Psalm 50:15 promises that calling on God in trouble brings deliverance, as exemplified by Moses' cry here.