1 Corinthians 8 has very strong Trinitarian/Binitarian implications.
To Paul, the person who “loves God” (1 Cor 8.3) knows that “there is no God but one” (1 Cor 8.4). His statements here encapsulate the monotheistic essence of Judaism, the Shema (“Hear, O Israel: The LORD our God, the LORD is one. You shall love the LORD your God with all your heart and with all your soul and with all your might,” Deut 6.4-5). The allusions made to idolatry, to loving God, and believing that God is one removes any uncertainty that Paul is drawing here on Deut 6.4-5.
Paul writes in vv. 5-6,
‘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.” For although there may be so-called gods in heaven or on earth—as indeed there are many “gods” and many “lords”— 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.’
Notice the contrast Paul makes between those heathen who have “many ‘gods’ and many ‘lords’—yet for us there is one God… one Lord.” In such a context where the Shema is central (idolatry, loving God, God is one), it would be self-defeating for Paul to do anything but embrace together the “one God” and “one Lord” in union, or as B.B Warfield puts it,
“Obviously, this ‘one God, the Father,’ and ‘one Lord, Jesus Christ,’ are embraced together in the one God who alone is. Paul’s conception of the one God, whom alone he worships, included, in other words, a recognition that within the unity of His being, there exists such a distinction of Persons as is given us in the ‘one God, the Father” and the ‘one Lord, Jesus Christ.’”
Had Paul wished to distinguish the "one God" from the "one Lord" so that there were in effect two sovereigns then his argument makes little sense. How then would Paul be any different than those heathen who have "many 'gods' and many 'lords'"?
Paul’s play on words in v. 6 makes this union of the “one God” and the “one Lord” even more apparent. Bauckham explains,
“that God is not only the agent or efficient cause of creation ('from him are all things') and the final cause or goal of all things ('to him are all things'), but also the instrumental cause ('through him are all things') well expresses the typical Jewish monotheistic concern that God used no one else to carry out his work of creation. By Paul's reformulation in 1 Corinthians 8:6, he includes Christ in this exclusively divine work of creation by giving to him the role of instrumental cause.” (God Crucified: Monotheism & Christology, 38-39)
In drawing upon the monotheistic concept that God alone created the universe (Isaiah 44.24, 4 Ezra 3.4), Paul attributes to Christ a role in creation which Jews would commonly attribute to God (Heb 2.10, Rom 11.36). For Paul to include the “one Lord, Jesus Christ” in the divine work of creation places Him squarely in a unique union with the “one God, the Father.” Perhaps Bauckham puts it best, “the unique identity of the one God consists of the one God, the Father, and the one Lord, his Messiah…” (Jesus and the God of Israel, p. 101).
Adding further credence to this is the fact that Paul goes on to speak about the relationship between the Corinthians and the “one Lord” Jesus over against idolatry (10.19-22),
“You cannot drink the cup of the Lord and the cup of demons. You cannot partake of the table of the Lord and the table of demons. Shall we provoke the Lord to jealousy? Are we stronger than He?” (1 Cor 10.21-22 c.f. Deut 32.21, Malachi 1.7-12)
The “Lord” that is spoken of here is most naturally taken to refer to Jesus for various reasons:
(i) Up to this point in Paul’s letter it is Jesus that is referred to as the “one Lord,” “the Lord of glory,” et al.
(ii) Paul uses this language of “the cup of the Lord” later in his letter to the Corinthians where it is Jesus who is the referent (1 Corinthians 11.27-28 c.f. 1 Corinthians 10.16-17, 2 Corinthians 6.15-16).
(ii) Paul uses this language of “the cup of the Lord” later in his letter to the Corinthians where it is Jesus who is the referent (1 Corinthians 11.27-28 c.f. 1 Corinthians 10.16-17, 2 Corinthians 6.15-16).
(iii) For Paul to refer to Jesus’ involvement in Israel’s redemptive history makes it clear who the “Lord” is in this passage. According to Paul, Christ is “the rock” (1 Cor 10.4) that accompanied the Israelites in the wilderness, and goes so far to even warn the Corinthians, “We should not test Christ, as some of them did—and were killed by snakes.” There seems to be a connection between testing Christ (1 Cor 10.9), and provoking the Lord (1 Cor 10.22).
(iv) Complimenting this is Paul’s utilization of κύριος (“Lord”) for Jesus repeatedly throughout 1 Corinthians which alludes to Old Testament texts involving the Divine Name (1 Corinthians 1.2 [c.f. Joel 2.32]; 1 Corinthians 2.16 [c.f. Isaiah 40.13]; 1 Corinthians 6.11 [c.f. Isaiah 45.23]).
(iv) Complimenting this is Paul’s utilization of κύριος (“Lord”) for Jesus repeatedly throughout 1 Corinthians which alludes to Old Testament texts involving the Divine Name (1 Corinthians 1.2 [c.f. Joel 2.32]; 1 Corinthians 2.16 [c.f. Isaiah 40.13]; 1 Corinthians 6.11 [c.f. Isaiah 45.23]).
