Exodus 13:11 in the King James Version
And it shall be when the LORD shall bring thee into the land of the Canaanites, as he sware unto thee and to thy fathers, and shall give it thee,
Context
10 You shall therefore keep this ordinance in its season from year to year.
11 “It shall be, when the LORD brings you into the land of the Canaanite, as he swore to you and to your fathers, and will give it to you,
12 that you shall set apart to the LORD all that opens the womb, and every firstborn that comes from an animal which you have. The males shall be the LORD’s.