The Shema, so called because it is the first word in Hebrew and means Listen! Or Hear!, is the earliest biblical creed and one of the most famous for both Jews and Christians. Its very brevity belies its immense profundity:
שְׁמַע יִשְׂרָאֵל יהוה אֱלֹהֵינוּ יהוה אֶחָד
Ἄκουε, Ἰσραήλ· Κύριος ὁ θεὸς ἡμῶν Κύριος εἷς ἐστιν.
Hear, O Israel: The Lord our God, the Lord is one.
In the local context of Deut 6, it functions as the bedrock foundation for hearing, obeying and teaching the commandments and instructions of the Lord. It is not without its own interpretive questions, however, the most discussed being whether or not it means that Yahweh alone is God versus all the false gods of the ANE, or whether God is one in nature, undivided, again vs. the polytheism of the nations of the ANE. I believe that both are valid interpretations and applications of the text.
With this in mind, consider Paul’s use of the Shema in 1 Cor 8:4-6
Περὶ τῆς βρώσεως οὖν τῶν εἰδωλοθύτων, οἴδαμεν ὅτι οὐδὲν εἴδωλον ἐν κόσμῳ καὶ ὅτι οὐδεὶς θεὸς εἰ μὴ εἷς. 5 καὶ γὰρ εἴπερ εἰσὶν λεγόμενοι θεοὶ εἴτε ἐν οὐρανῷ εἴτε ἐπὶ γῆς, ὥσπερ εἰσὶν θεοὶ πολλοὶ καὶ κύριοι πολλοί, 6 ἀλλʼ ἡμῖν εἷς θεὸς ὁ πατὴρ ἐξ οὗ τὰ πάντα καὶ ἡμεῖς εἰς αὐτόν, καὶ εἷς κύριος Ἰησοῦς Χριστὸς διʼ οὗ τὰ πάντα καὶ ἡμεῖς διʼ αὐτοῦ.
4 Therefore, as to the eating of food offered to idols, we know that “an idol has no real existence,” and that “there is no God but one.” 5 For although there may be so-called gods in heaven or on earth—as indeed there are many “gods” and many “lords”— 6 yet for us there is one God, the Father, from whom are all things and for whom we exist, and one Lord, Jesus Christ, through whom are all things and through whom we exist.
Like practically all the good theology in the NT, 1 Cor 8:4-6 arises from a very practical ethical issue facing the church, whether or not it was proper to eat food that had been offered first to idols. That raises the question of the existence of the θεοί (gods) whom the idols are supposed to represent (the pagan belief was that the god really was present in the idol). Paul’s answer to that is to give an obvious paraphrase of the Shema, especially:
οὐδεὶς θεὸς εἰ μὴ εἷς, “there is no god except the One.”
Paul then goes on to expand on his statement, first making clear that while there may be many things that are called (λεγόμενοι) gods and lords in the minds of the various pagan cultures of ancient Rome, there is in fact, only one Lord – well, that’s what we would expect him to say if in fact he is contrasting the truth of the Shema with pagan understanding, but instead he claims that there is one God, and that is the Father, and with special emphasis on the Father as the source of all things (ἐξ οὗ τὰ πάντα, “from whom are all things”). But he doesn’t stop there. He goes on to say καὶ εἷς κύριος Ἰησοῦς Χριστὸς διʼ οὗ τὰ πάντα καὶ ἡμεῖς διʼ αὐτοῦ, “and one Lord Jesus Christ, through whom are all things, and we through him.”
One could preach multiple sermons on the truth of this passage or write a book length treatise, but here I just want to make a few simple observations. The connection with Deut 6:4 is here obvious, and the truth of one God the Father and one Lord Jesus Christ stands in contrast to the many gods and lords of paganism. What Paul does is take the Shema and split it into two parts, referring to the Father as one God and the Son as one Lord. Anyone familiar with the OT background here, and particular the LXX translation of the OT, would know that in the original context κύριος, Lord, translates Yahweh. We are getting some profound new revelation here, that the Father is God and that Jesus is Lord, Yahweh. The special title of the Father which designates his role in the Trinity is that of God, and the special title of Jesus is that of Lord. Notice also the prepositional phrases which indicate that the Father is the source of creation and that Jesus is the instrumental means of creation. In the OT it is simply Yahweh who is presented as the creator who brings all things into existence. In the NT it is both the Father and the Son, with differing roles in creation, but both treated as creator. It is language like this which informed the creed:
Πιστεύομεν εἰς ἕνα Θεὸν Πατέρα παντοκράτορα
ποιητὴν οὐρανοῦ καὶ γῆς ὁρατῶν τε πάντων καὶ ἀοράτων·
καὶ εἰς ἕνα Κύριον Ἰησοῦν Χριστὸν
τὸν υἱὸν τοῦ Θεοῦ τὸν Μονογενῆ,
τὸν ἐκ τοῦ Πατρὸς γεννηθέντα πρὸ πάντων τῶν αἰώνων,
Φῶς ἐκ Φωτός,
Θεὸν ἀληθινὸν ἐκ Θεοῦ ἀληθινοῦ,
γεννηθέντα οὐ ποιηθέντα,
ὁμοούσιον τῷ Πατρί,
δι’ οὗ τὰ πάντα ἐγένετο·
We believe in one God,
the Father almighty,
maker of heaven and earth,
of all things visible and invisible;
And in one Lord, Jesus Christ,
the only begotten Son of God,
begotten from the Father before all ages,
light from light,
true God from true God,
begotten not made,
of one substance with the Father,
through Whom all things came into existence…
One more observation, and that is the description of the Father and the Son are in two rather nicely balanced clauses, identical word order emphasizing their “oneness” and the prepositional phrases perfectly aligning with one another. Beginning with ἀλλά in vs. 6, there are exactly 20 syllables in each clause. This rhetorical balance further highlights the equality between the Father and the Son.