Charles Ellicott Commentary 1 Corinthians 10:2

"and were all baptized unto Moses in the cloud and in the sea;" — 1 Corinthians 10:2 (ASV)

Were all baptized unto Moses.—The weight of evidence favors the middle voice for the verb used here, which signifies that they all voluntarily had themselves baptized to Moses. Moses was God’s representative under the Law, and so they were baptized to him in their voluntarily joining with that “Church” of God which marched beneath the shadow of the cloud and passed through the waters of the sea—just as Christians are baptized to Jesus Christ, He being (in a higher sense, both in kind and in degree) God’s representative in the New Dispensation.

The “cloud” and the “sea” refer to the cloud that overshadowed the Israelites (Exodus 13:21, and see Numbers 14:14), and the passage through the Red Sea (Exodus 13:22; Numbers 35:8).