'Free will' in the Bible

"Tell Aaron, his sons, and all the Israelis that when a person from the house of Israel or from the resident aliens living in Israel brings his offering to the LORD as a whole burnt offering (whether in fulfillment of a promise or a free will offerings),

"If a person brings a peace offering sacrifice to the LORD to fulfill a vow or a free will offering from the herd or the flock, it is to be sound in order to be accepted, without any defect in it.

"You may offer a bull or lamb that has one limb longer than the other or that is stunted as a free will offering, but it's not acceptable in fulfillment of a promise.