Deuteronomy 23:23

23:23 Whatever you vow, you must be careful to do what you have promised, such as what you have vowed to the Lord your God as a freewill offering.

Deuteronomy 24:10-11

24:10 When you make any kind of loan to your neighbor, you may not go into his house to claim what he is offering as security. 24:11 You must stand outside and the person to whom you are making the loan will bring out to you what he is offering as security.

Deuteronomy 33:10

33:10 They will teach Jacob your ordinances

and Israel your law;

they will offer incense as a pleasant odor,

and a whole offering on your altar.