Did the apostle Paul think of Christ as an angel who became human and then returned to heaven? A minority of scholars have thought this the case.
When Paul refers to Christ as the “heavenly man” (epaouranios) in 1 Cor 15.48-49 it could imply that Christ is the heavenly archetype of Adam or else a heavenly being akin to an angel.
The sending of the Son (Rom 8.3; Gal 4.4) is perhaps the sending of an angelic son like the “sons of God” in the Hebrew Bible (Job 1.6; 2.1; 38.7; Ps 82.6; 89.6).
Elsewhere, Paul praises the Galatians who “welcomed me as an angel of God, as Christ Jesus” (Gal 4.14) and it is suggested the association between receiving an angel and Christ is because Christ is a species of angel.
In addition, some attempt to read the Christ-hymn of Phil 2.6-11 as narrating the story of the descent, anthropomorphic appearance, and super-exaltation of an angelic being to the upper echelons of the heavenly hierarchy.
Finally, much often made of the fact that Paul addresses Jesus as “God” (Rom 9.5) and applies prominent Yahweh-texts to him to address him as “Lord” (e.g., Phil 2.11; 1 Cor 8.6). Yet calling an angel “Lord” (Zech 1.9; 4.4-5; 4 Ezra 2.44; Jos. Asen. 17.9; Apoc. Zeph. A) or “God” (Gen 31.11-13; Exod 3.1-22; Jdgs 13.22; Jos. Asen. 17.10; 4Q402 1 2.30-46; 11QMelch 2.10, 24-25) can be done without thinking twice. Even applying a Yahweh-text to a heavenly figure is not without precedent (Mic 1.4 with 1 Enoch 52.6; Isa 52.7; 61.1-3; Ps 7.7-8; 82.1-2; 110.1 with 11QMelch 1–2; Exod 15.11; Isa 44.7; Ps 89.7 with 4Q491c 8-13).
Yet, in regard to Pauline christology as a whole, an angel-Christology does not offer the most coherent way of articulating his christological convictions.
First, the main thrust in 1 Cor 15.48-49 is that Christ is the eschatological deliver in heaven, how believers will one day be conformed to his image, and he will return from heaven to establish God’s kingdom. His heavenly residence does not entail to angelic qualities.
Second, equating Christ with an angel of God based on Gal 4.14 builds far too much on far too little.
Third, what is predicated of Christ in Phil 2.6-11 in terms of his heavenly position as “equal with God,” undergoing something closer to incarnation than merely angelic anthropophany, and super-exaltation to is not truly paralleled in Jewish angelology. Qumran’s Michael is the angelic representative of Israel and his exaltation mirrors Israel’s military supremacy over the nations (1QM 17.7-8), while Melchizedek remains YHWH’s agent against Belial who is his true counter-part (11QMelch 2.12-14). Paul exceeds these feats of angelic exaltation by applying Isaianic language to Jesus in Phil 2.9-11, by identifying Jesus with the God who says ‘I am God, and there is no other’ (Isa 45.22), the God who expects universal obeisance and allegiance (Isa 45.23), and the God who shares his glory with no other now shares it with Jesus (Isa 42.8). Plus, to which of the angels does Paul, or any Jewish author say: has their own “day” of judgment (Phil 1.6, 10; 2.16); of whom people declare they are imprisoned for (Phil 1.13); who they proclaim out of love (1.16), an angel who’s spirit helps them (1.19); an angel who is exalted in their body (1.20); an angel whom they live for, participate in his sufferings, anticipate the power of his resurrection, and relish being with beyond death (1.21-23; 3.10); an angel who they boast upon (1.26; 3.3); whom they consider gain and everything else loss (3.7-9); who made them his own (3.12); an angel who “will transform the body of our humiliation that it may be conformed to the body of his glory” and who “by the power that also enables him to make all things subject to himself” (Phil 3.21). This language of devotion here is more appropriate for a Jewish author in his or her relation to Yahweh rather than to the angel of Yahweh, yet it describes Jesus.
Fourth, it would be straining some monotheistic sensibilities to include an angelic figure within the shema (Dt 6.5) as Paul does with Christ (1 Cor 8.6). The knowledge of the one God over and against idols (1 Cor 8.1-5) includes the priority and prominence of “one God, the Father” as Creator along with “one Lord, Jesus Christ” as demiurge and deliverer, but only in the context of their unity as they operate “for us.” Angels do not have a part in monotheistic confession, demiurgy, and a mode of deliverance that puts the delivered in a relationship with them!
Fifth, more pointedly, Paul habitually pairs God the Father with Jesus his Son (1 Cor 1.3, 9; 8.6; 2 Cor 1.2-3; 11.31; Gal 1.1-3; 4.6; 1 Thess 1.1-3; 2 Thess 1.1-2) while angels are rarely mentioned and if anything are Christ’s attendants at his parousia (1 Thess 4.16; 2 Thess 1.7; cf. 1 Tim 5.21). Interesting too is how Paul conceives of the Father’s love in Christ as operating above angels, rulers, and powers (Rom 8:38-39). In other words, Paul consistently places Christ beside God the Father, while nothing he says implies that Christ is merely first among equals in an angelic hierarchy.
Tilling’s conclusion is apt: “There is no angel or intermediary being of any kind in any text that parallels the way Paul speaks of this Christ-relation. Rather the way Paul describes the relation between Christ and Christians is analogous only to the relation between Israel and YHWH.”
 Cf. e.g., Horbury, Jewish Messianism, 113, 120; Charles Gieschen, Angelomorphic Christology: Antecedents and Early Evidence (AGAJU, 42; Leiden: Brill, 1998); Susan R. Garrett, No Ordinary Angel: Celestial Spirits and Christian Claims (New Haven, CT: Yale university Press, 2008); Bart D. Ehrman, How Jesus Became God: The Exaltation of a Jewish Preacher from Galilee (New York: HarperOne, 2014), 251-69; Emma Wasserman, Apocalypse as Holy War: Divine Politics and Polemics in the Letters of Paul (New Haven, CN: Yale University Press, 2018), 132-37.
 Cf. Philo, Leg. All. 1.31.
 Garrett, No Ordinary Angel, 11.
 Horbury, Jewish Messianism, 113, 120; Ehrman, How Jesus Became God, 262-66; Wasserman, Apocalypse as Holy War, 132-35; esp. James A. Sanders, “Dissenting Deities and Philippians 2:1-11,” JBL 88 (1969): 279-90.
 Cf. Fee (Pauline Christology, 299-31) rightly sees a progression of examples from an angel to Christ rather than an identification of Christ as an angel. Hannah (Michael and Christ, 155-56) says “The grammar certainly permits this [i.e., Christ is an angel], but it is hardly compelling.”
 That is assuming res rapta interpretation whereby “form of God” and “equality with God” are parallel and something already possessed.
 In Phil 2.7 the language of “becoming” like human beings (gimomai) and “as a human being” (hōs anthropos) is indicative of ontological transformation not merely outward appearance. The case builds with Gal 4.4 and Rom 1.3. which refer to Jesus’s human birth.
 Chris Tilling, “Misreading Paul’s Christology: Problems with Ehrman’s Exegesis,” in How God Became Jesus: The Real Origins of Belief in Jesus’ Divine Nature (Grand Rapids, MI: Zondervan, 2014), 145-46.
 Here I disagree with McGrath (The Only True God, 39-44) that Paul includes Jesus alongside God as a deputy rather than beside God as an equal in the shema. Paul, like Philo (Her. 166; Plant. 86; Somn. 163; Abr. 121, 124; Mos. 2.99-100; Spec. Leg. 1.30, 307), splits the creative and executive functions of Israel’s one God between the Father and Christ.
 Samuel Vollenweider, “Vom israelitischen zum christologischen Monotheismus. Überlegungen zum Verhältnis zwischen dem Glauben an den einen Gott und dem Glauben an Jesus Christus,” in Antike und Urchristentum: Studien zur neutestamentlichen Theologie in ihren Kontexten und Rezeptionen (WUNT 436; Tübingen: Mohr/Siebeck, 2020), 130. Cf. Tilling, Paul’s Christology, 90-92 where he argues that Paul includes Christ in the same relational dynamic of love and knowledge as Israel had with Yahweh.
 Tilling, “Misreading Paul’s Christology,” 144.