Malachi 1:14

Some consider that two cases are mentioned in this verse. (1) One who acts deceitfully (by offering a female as a burnt offering, which is contrary to the Law, while there is in his flock a male); (2) and one who makes a vow (to offer a sacrifice of peace offerings, for which either a male or a female was allowable, provided it were without a blemish: Leviticus 22:23), and then offers an animal that has a blemish. But it is better to understand but one case to be mentioned — viz., that of a man who vows, and while he has a male in his flock offers a female with a blemish. A female without blemish would be admissible as a vow offering, but a male without blemish would be the most valuable, because it could be offered as a burnt offering, whereas a female could not; while a female with a blemish would be the very worst, and actually illegal. A man is not bound to make a vow, but if he make one his offering should be of the very best, just as he would not dare to offer to a king or to his ruler (Malachi 1:6) anything but the best. How cursed, then, must he be who, while he possesses the best, deliberately makes a vow to God, and then offers Him the very worst.