Three months after the Israelites left Egypt, they must still have been buzzing about their deliverance. Then God did something they did not expect. He took Moses up into the mountains for forty days. That act did not make sense to the people. To make matter worse, God issued a clear but seemingly inexplicable instruction. While He met with Moses at Mount Sinai, He told the people in no uncertain terms, "Take heed to yourselves, that you do not go up to the mountain or touch it's base; whoever touches the mountain shall surely be put to death" (Exodus 19:12). Furthermore, God did not give the people any details about His meeting with their leader, Moses.
1) LACK OF TRUST IN GOD LEADS TO FALSE WORSHIP