Albert Barnes Commentary Deuteronomy 12:21

"If the place which Jehovah thy God shall choose, to put his name there, be too far from thee, then thou shalt kill of thy herd and of thy flock, which Jehovah hath given thee, as I have commanded thee; and thou mayest eat within thy gates, after all the desire of thy soul." — Deuteronomy 12:21 (ASV)

If the place ... - Rather, “Because, or since, the place will be too far from you.” The permission given in (Deuteronomy 12:15–16) is repeated, and the reason for it is assigned.