Why is 'the Lord thy God' mentioned in the first five commandments but not the last five?
The supplied context does not explain why. It only observes that all five of the first commandments are connected with the statement “the Lord thy God,” while the last five never mention it. The text tells readers to be aware of that distinction but gives no reason for it.
Les explains that when reading the Ten Commandments, verse 2 begins, “I am the Lord thy God.” He points out that all five of the First Commandments will be connected with that statement, the Lord thy God, but that in the last five it is never mentioned. He then reads the first and second commandments, where the phrase appears again, but he does not provide a reason why the first five include it and the last five do not.