Deuteronomy 6:4 isn't necessarily dealing with God's type of existence. The point is that YHWH is their God and only YHWH is their God, not that he is the only god. It deals with which god they are to obey.
Deut 6:5 Love the LORD (YHWH) your God with all your heart and with all your soul and with all your strength.
Deut 6:13 Fear the LORD (YHWH) your God, serve him only and take your oaths in his name.
Deut 6:14 Do not follow other gods, the gods of the peoples around you;
Does the Shema (Deut 6:4) Prove There are No Other gods?
International Standard Version
"Listen, Israel! The LORD is our God, the LORD alone.
™ Version 4.2
