TSK · Exodus 34:20

then you must give over to the LORD the first offspring of every womb. Every firstling of a beast that you have– the males will be the LORD’s.

When Pharaoh stubbornly refused to release us, the LORD killed all the firstborn in the land of Egypt, from the firstborn of people to the firstborn of animals. That is why I am sacrificing to the LORD the first male offspring of every womb, but all my firstborn sons I redeem.’

“Take the Levites instead of all the firstborn males among the Israelites, and the livestock of the Levites instead of their livestock. And the Levites will be mine. I am the LORD.

Three times a year all your males must appear before the LORD your God in the place he chooses for the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Shelters; and they must not appear before him empty-handed.

But the king said to Araunah,“No, I insist on buying it from you! I will not offer to the LORD my God burnt sacrifices that cost me nothing.”So David bought the threshing floor and the oxen for fifty pieces of silver.