Kli Yakar (Bereishis 1:1) Rabbi Yitschak said, "It was not necessary to begin the Torah, etc. but rather so that the nations should not say, 'you are thieves, etc.'" And it is difficult; and what about it, if they will say, "you are thieves," and because of this, the order of the Torah should be changed? The answer to this is that this matter brings heresy to the world, since they will say, "there is no law and no Judge" in the world and 'whoever is strongest prevails;' since if the world had a Ruler, who sets up its matters - it comings and goings - why did He not protest against you when you took by force - by way of theft - the lands of the seven Canaanite nations? Since it is for this reason that the judgment of the generation of the flood was not sealed except on account of theft, as it is stated (Proverbs 28:24), "One who steals from his father and mother and says 'it is not a transgression' is the companion of a destructive person;" since the reason this sin is greater than others is not because of the sin itself, but rather because of the evil that comes out of it; as the sinner who steals does not place guilt upon himself and says, "there is no transgression, since there is no God that judges in the world;" and therefore he is the companion of a destructive person, which means to say, he is a companion of the generation of the flood, as it is stated about them (Genesis 6:12), "since all flesh destroyed its way," since they also denied a principle of faith and said (Job 21:15), "What is the Omnipotent, that we should serve Him, etc." And this is what [brought] them to practice extortion and theft in the world. And because the prevention of theft is fundamental to all of faith, therefore the Holy One, blessed be He, made it come early and warned about it in the first commandment of (Exodus 12:2), "This month will be for you;" as over there, it is stated (Exodus 12:21), "And bring close and acquire for yourselves sheep," meaning from yours, and not from stolen ones; so explained the Ba'al HaTurim. And so too, Yitschak, when he commanded two kid goats to be brought to him, to make from them a Pesach sacrifice, he said (Genesis 27:3), "And hunt for me venison;" Rashi explained, from what is unowned and not from what is stolen, but since Esav's heart was not like that, it appeared to him that he could rather "hunt venison to bring," even from what is stolen; hence G-d caused that he should not bring it, but rather that Ya'akov should do so, as he was careful about theft. So too, the ox that Adam sacrificed, the Sages say that it had one horn on its forehead; to show that Adam too was one 'horn' in the world - meaning to say that he was by himself in the world - and did not steal from any creature; therefore, his sacrifice was accepted. And all this is in order to push away theft and robbery which brings heresy and apostasy.