Leviticus 27:30-33

Thomson(i) 30 The whole tenth of the land, both of the produce of the land, and of the fruit of the trees, is for the Lord. It is dedicated to the Lord. 31 And if any man chuse to redeem his tenth by purchase, he shall add to the valuation a fifth, and it shall be his. 32 Now the whole tenth of herds and flocks; even every one which in numbering shall come under the rod, that tenth shall be dedicated to the Lord. 33 Thou shalt not change a good for a bad, nor a bad for a good; and if thou shalt actually make an exchange, that given in exchange shall also be consecrated, and shall not be redeemed.