spot the difference

EXODUS 20:2-17 1. Thou shalt have no other gods before me. 2. Thou shalt not make unto thee any graven image. 3. Thou shalt not take the name of the LORD thy God in vain. 4. Remember the sabbath day, to keep it holy. 5. Honour thy father and thy mother: that thy days may be long upon the land which the LORD thy God giveth thee. 6. Thou shalt not kill. 7. Thou shalt not commit adultery. 8. Thou shalt not steal. 9. Thou shalt not bear false witness against thy neighbour. 10. Thou shalt not covet.

EXODUS 34:12-27 1. Take heed to thyself, lest thou make a covenant with the inhabitants of the land whither thou goest, lest it be for a snare in the midst of thee: But ye shall destroy their altars, break their images, and cut down their groves: 2. For thou shalt worship no other god: for the LORD, whose name is Jealous, is a jealous God: 3. Thou shalt make thee no molten gods. 4. The feast of unleavened bread shalt thou keep. Seven days thou shalt eat unleavened bread, as I commanded thee, in the time of the month Abib. 5. All that openeth the matrix is mine; and every firstling among thy cattle, whether ox or sheep, that is male. 6. But the firstling of an ass thou shalt redeem with a lamb: and if thou redeem him not, then shalt thou break his neck. 7. Six days thou shalt work, but on the seventh day thou shalt rest. 8. And thou shalt observe the feast of weeks, of the firstfruits of wheat harvest. 9. Thou shalt not offer the blood of my sacrifice with leaven; neither shall the sacrifice of the feast of the passover be left unto the morning. 10. Thou shalt not seethe a kid in his mother's milk.

How can those two lists be so utterly different? When Moses dropped the first set of tablets, the second set was supposed to be a duplicate, remember? So who decided which were to be the Ten Commandments?! And how did they decide? Did someone take a vote? Toss a coin? Arm wrestle for their favorites? To repeat, there are no Ten Commandments.