Charles Ellicott Commentary Acts 7:36

"This man led them forth, having wrought wonders and signs in Egypt, and in the Red Sea, and in the wilderness forty years." — Acts 7:36 (ASV)

After that he had shewed wonders and signs.—The two nouns are joined together, as in Deuteronomy 6:22 and Matthew 24:24. The words express different relations, perhaps, of the same phenomena, rather than phenomena specifically different; the first emphasizing the wonder which the miracle produces, and therefore corresponding more strictly to that word; the latter, the fact that the miracle is a token or evidence of something beyond itself. (See also Acts 2:22 and Acts 6:8.)

In the Red sea.—It may be worthwhile to note that the familiar name comes to us not from the Hebrew word, which means, literally, the Weed Sea, but from the LXX version, which Stephen, as a Hellenistic Jew, used, and which provided the word Erythraean, or red. This word had been used by Greek travelers from Herodotus onward.

Why the name was given is an unsolved problem. Some have referred it to the color of the coast; some to that of the seaweed; some to an attempt to give an etymological translation of its name as the Sea of Edom (Edom meaning “red,” as in Genesis 25:25 and Genesis 36:1); and some to a supposed connection with an early settlement of Phoenicians, whose name had the same significance for the Greeks.