'Two' in the Bible

Do you not know that the one who joins himself to a prostitute is one body with her? For He says, “The two shall be one flesh.”

If anyone speaks in a tongue, it should be limited to two or at the most three, and each one speaking in turn, and one must interpret [what is said].

Let two or three prophets speak [as inspired by the Holy Spirit], while the rest pay attention and weigh carefully what is said.