[Songcraft]

Likewise, while the Ten Commandments had not yet been revealed by Moses, children still obeyed and honored their mother and father, as later explicitly commanded in the Ten commandments (example - Isaac & Abraham).   But Adam and Eve would have been the only two people in the Old Testament who would not have been able to honor their human father and mother, as they didn't have any.

[Mrs. Don-o]

They also didn’t have belly buttons. :o)