Even the Rabbis saw this. There is a kind of rueful parable put into the mouth of Korah, which shows just how binding and constricting and burdensome and impossible the demands of the law could be. ‘There was a poor widow in my neighbourhood who had two daughters and a field. When she began to plough, Moses [i.e. the law of Moses] said: “You must not plough with an ox and an ass together.” When she began to sow, he said: “You must not sow your field with mingled seed.” When she began to reap and to make stacks of corn, he said: “When you reap your harvest in your field, and have forgotten a sheaf in the field, you shall not go back to get it” [Deuteronomy 24:19], and “you shall not reap your field to its very border” [Leviticus 19:9]. She began to thresh, and he said: “Give me the heave-offering, and the first and second tithe.” She accepted the ordinance and gave them all to him. What did the poor woman then do? She sold her field and bought two sheep, to clothe herself from their fleece and to have profit from their young. When they bore their young, Aaron [i.e. the demands of the priesthood] came and said: “Give me the first-born.” So she accepted the decision, and gave them to him. When the shearing time came, and she sheared them, Aaron came and said: “Give me the first of the fleece of the sheep” [Deuteronomy 18:4]. Then she thought: “I cannot stand up against this man. I will slaughter the sheep and eat them.” Then Aaron came and said: “Give me the shoulder and the two cheeks and the stomach” [Deuteronomy 18:3]. Then she said: “Even when I have killed them I am not safe from you. Behold they shall be devoted.” Then Aaron said: “In that case they belong entirely to me” [Numbers 18:14]. He took them and went away and left her weeping with her two daughters.’ The story is a parable of the continuous demands that the law made upon people in every action and activity of life. These demands were indeed a burden.
William Barclay, The Gospel of Matthew, Third Ed., The New Daily Study Bible (Edinburgh: Saint Andrew Press, 2001), 19–20.