In chapter 20, God Himself spoke these 10 commandments from Mount Sinai, then commanded Moses to ascend the mountain, where God Himself wrote these 10 commandments on stone. While Moses was up in the mountain with God, He also gave Moses many more laws, as well as the pattern of the tabernacle, which comprises chapters 20-32. However, the Hebrews down at the base of the mountain, seeing that Moses delayed to come down from the mountain, decided in disbelief that he wasn't returning, and they erected a golden calf to worship as their god. When Moses descended and saw their idolatry, he casts the tablets of stone down, breaking them in pieces. So the first "version", which was actually the first "set", was destroyed. In chapter 34 God then told Moses to cut out two tablets like the first. And again, God Himself wrote the 10 commandments on this second set. However, the specific wording of the 10 commandments are not repeated again in chapter 34; their contents were originally given in chapter 20. Hence, the second "set". Perhaps notable is Deuteronomy (which is Moses' farewell address) chapter 5, where Moses repeats the 10 commandments. There are a few variations between Deuteronomy 5 and Exodus 20, but the variations are rhetorical. Overall, they are quite alike.

The ten commandments can also be found in the book of Deuteronomy 5:6-21

Anytime anything is repeated in the bible ist means it is very important- the more repeats the more important it is. The 10 commandmands are the basis of English common law whic is the basis of the US judicial system.