Compare Deuteronomy 5:22-31. Aaron Exodus 19:24 on this occasion accompanied Moses in drawing near to the thick darkness.
Exodus 20:22 to Exodus 23:33 is a series of laws which we may identify with what was written by Moses in the book called the book of the covenant, and read by him in the audience of the people Exodus 24:7.
The document cannot be regarded as a strictly systematic whole. Portions of it were probably traditional rules handed down from the patriarchs, and retained by the Israelites in Egypt.