Deuteronomy 6:4 reads like this in the ESV: “Hear, O Israel: The Lord our God, the Lord is one.” Both occurrences of “Lord” here are “Yahweh.” This translation, however, is not the only one possible. The reason for this is that the inter-relationships between the words is not explicit (McConville, pg. 140). Here it is in Hebrew:
שְׁמַע יִשְׂרָאֵל יְהוָה אֱלֹהֵינוּ יְהוָה אֶחָד׃
Now, the four interpretations that McConville lists are as follows: “The Lord is our God, the Lord alone;” “The Lord our God, the Lord is one;” The Lord is our God, the Lord is one;” and “The Lord our God is one Lord.” The first emphasizes the polemical edge against other religions. The second emphasizes the oneness of the Lord. The third emphasizes the possessiveness of one Lord on the part of Israel, and the fourth is very little different from the third. At any rate, one can say with certainty that oneness and Lordship go together, and that this one Lord is “our” Lord.
The question arises: does this formulation preclude the Trinity? The answer must be “no.” Moses, in this chapter, is very careful to contrast the polytheistic religions of the nations in Canaan with the monotheism of Israel. This is clear in verses 14-15. However, that there might be a plurality within the one God is not ruled out. Moses’ focus is polemics, not so much on saying everything about the number of God that could be said. After all, Deuteronomy occurs in the same section of the canonas Genesis 1, which plainly indicates that within God there is plurality.