24 and to offer a sacrifice in keeping with what is said in the Law of the Lord: “a pair of doves or two young pigeons.”a

Read Luke 2:24 Using Other Translations

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.
and to offer a sacrifice according to what is said in the Law of the Lord, "a pair of turtledoves, or two young pigeons."
So they offered the sacrifice required in the law of the Lord—“either a pair of turtledoves or two young pigeons.”