This is a well-known Midrash about the young Moses being a threat in the future to Pharaoh. So, to test this danger, they set before Moses objects. There are varying opinions on what these were – a gold rock, or an onyx which also varies in color. The one thing agreed on was there was a fiery red coal. If his hand went toward the rich stone, he would be a danger, and Pharaoh would have him killed. Next to Pharaoh was his daughter who had rescued Moses. On the other side were Pharaoh’s advisors Balaam and Jethro. As Moses moved his hand, the other attendee was a disguised archangel Gabriel who influenced Moses to move toward the coal, but unexpectedly, not only did his hand head for it, relieving Pharaoh of his fear, Moses suddenly picked it up and put it in his mouth and from then on, he stuttered. His brother Aaron would do the speaking for him.