John Gill Commentary Leviticus 11:1

"And Jehovah spake unto Moses and to Aaron, saying unto them," — Leviticus 11:1 (ASV)

And the Lord spoke to Moses, and to Aaron
The one being the chief magistrate, and the other the high priest, and both concerned to see the following laws put into execution; according to Jarchi, the Lord spoke to Moses that he might speak to Aaron; but being now in office, and one part of his office being to distinguish between clean and unclean, the following discourse is directed equally to him as to Moses:

saying to them ;
as follows.