The Lord is unique. There is no other God besides him.
This teaching repeats the first two commandments (5:6–8; Exodus 20:2–4). It also prepares the way for the Shema (a Hebrew word that means “Hear”). The Shema begins with the words, “Hear, O Israel: The LORD our God, the LORD is One” (Deuteronomy 6:4–5).
God’s uniqueness needed to be clearly stated. The nations around Israel worshiped many gods. Israel was called to worship the Lord alone.