Exodus 15 · a question people ask
Is the tree at Marah a picture of the cross?
Exodus says only this: "The LORD showed him a tree, and he threw it into the waters, and the waters were made sweet" (15:25). The New Testament never mentions Marah. Christians read the tree in two main ways. Both agree that it was the LORD who showed Moses the tree (15:25), and that the LORD calls himself the one "who heals you" (15:26).
How Christians read it
Where Christians differ, Favor sets out the main views side by side and doesn't pick one.
A picture of the cross
Those who hold this view note that the New Testament calls the cross a tree. Peter writes that Jesus "bore our sins in his body on the tree", and "You were healed by his wounds" (1 Peter 2:24). Paul writes, "Cursed is everyone who hangs on a tree" (Galatians 3:13), and Peter tells the council that they killed Jesus, "hanging him on a tree" (Acts 5:30). They see the tree that made bitter water sweet as a picture of the cross.
1 Peter 2:24 · Galatians 3:13 · Acts 5:30
What the LORD used that day
Those who hold this view note that when Paul draws lessons from Israel's journey out of Egypt ("these things were our examples", 1 Corinthians 10:6), he names the cloud, the sea, the food, the drink and the rock (1 Corinthians 10:1-4), but not Marah. They read the tree as what the LORD chose to use that day, as he had used Moses' rod at the sea (14:16).
1 Corinthians 10:1-6 · Exodus 14:16
The verses
“Then he cried to the LORD. The LORD showed him a tree, and he threw it into the waters, and the waters were made sweet. There he made a statute and an ordinance for them, and there he tested them. He said, “If you will diligently listen to the LORD your God’s voice, and will do that which is right in his eyes, and will pay attention to his commandments, and keep all his statutes, I will put none of the diseases on you which I have put on the Egyptians; for I am the LORD who heals you.””