'Pair' in the Bible

Thus says Yahweh: "For three transgressions of Israel, yes, for four, I will not turn away its punishment; because they have sold the righteous for silver, and the needy for a pair of shoes;

that we may buy the poor for silver, and the needy for a pair of shoes, and sell the sweepings with the wheat?'"

and to offer a sacrifice according to that which is said in the law of the Lord, "A pair of turtledoves, or two young pigeons."