What was God preparing Israel for at Mount Sinai in Exodus?
At Mount Sinai, God was preparing Israel to set up the ecclesiastical part of the law, which established their temple worship. They had already received the Ten Commandments and some civil law. This worship would be a tabernacle—a tent—which is temporary.
Les teaches that God was preparing the nation of Israel, several million strong, gathered around Mount Sinai. They had now been given the law, the Ten, and God had already begun to give them a certain amount of the civil law in the intervening chapters. He was getting ready to set up the ecclesiastical part of the law, which establishes their temple worship. Since it would be a tabernacle—another word for tent—it was temporary.