Albert Barnes' Notes on the Whole Bible - 1 Corinthians 10:2
And were all baptized - In regard to the meaning of the word “baptized,” see the note at Matthew 3:6. We are not to suppose that the rite of baptism, as we understand it, was formally administered by Moses, or by any other person, to the Jews, for there is not the least evidence that any such rite was then known, and the very circumstances here referred to forbid such an interpretation. They were baptized “in the cloud” and “in the sea,” and this cannot be understood as a religious rite... read more
The Pulpit Commentary - 1 Corinthians 10:2
Baptism unto Moses. The expression used here is a singular and suggestive one, and one that seems to require an enlargement of our associations with the term "baptized." "Were all baptized unto Moses in the cloud and in the sea." It may be noted that more precisely the passage should read, "all baptized themselves unto Moses." St. Paul sees, in the incidents of the crossing of the Red Sea under the guidance of the pillar cloud, a symbol of that Christian confession which puts us wholly... read more