The expression ἐν μορφῇ θεοῦ ὑπάρχων in the first half of v. 6, here translated “although he existed in the form of God,” raises two questions: (1) the meaning of (“form”) and (2) the force of the participle ὑπάρχων (lit., “existing”). Commentators have balked at the plain meaning of μορφὴ θεοῦ (“form of God”), since μορφή denotes not “essence”21 but “outward appearance” or visible “shape,” implying that Paul, a Jew, thought God could be “perceived by the senses.” To be sure, there is an important tradition in ancient Israelite and Jewish religion that God is beyond human perception. But there is an equally prominent tradition that God or at least God’s “Glory” (כבוד, kābôd; LXX δόξα) can be seen.

According to Isa 6:1-3, God has a gigantic humanlike body: “I saw Yahweh sitting on a throne, high and lofty, and the hem of his robe filled the temple.” Accord- ing to Ezek 1:26-28 this body is not God’s per se but the luminous “image of the likeness of the Glory [כבוד] of Yahweh.” In 1 Enoch 14:20, the figure seated on “the lofty throne” is identified as the “Great Glory” (ἡ δόξα ἡ μεγάλη), whose “raiment was like the appearance of the sun.” Angels were imagined to have similar humanlike forms that increased in grandeur and radiance the closer they were stationed to God’s throne. To say then, as Paul does, that Christ existed in “the form of God” is simply to say that, prior to his self-humbling metamorphosis, Christ enjoyed a luminous appearance of the sort a powerful angel might possess. Philo uses much the same language in his account of the burning bush in Mos. 1.66: “and at the center of the flame was a form [μορφή] that was supremely beautiful . . . an image most God-like in appearance [θεοειδέστατον] . . . but let it be called an angel [καλείσθω δὲ ἄγγελος].”

1. Numerous tortured attempts have been made to read the notion of an invisible “essence” back into the term, but none convinces. Lightfoot, for example, notes the use of μορφή and σχῆμα (which appears in the next verse) in Aristotle, where μορφή denotes an outward appearance that is unchanging and σχῆμα denotes an outward appearance that changes. It is not clear what this approach gains, since in either case outward appearance is in view. Further, whatever one decides about Aristotle, for Paul μορφή and σχῆμα are synonymous, and the point of Phil 2:6-8 is that Christ precisely did change “form” (μορφή)! It might be objected that Christ did not change form so much as add a form: “taking [λαβών] the form of a slave.” But that is to read too much into the idiom. According to Euripides, Hel. 19, Zeus similarly “took” the form of a swan (μορφώματ ̓ ὄρνιθος λαβών). Not all attempts are this sophisticated. Barth, with characteristic selectivity, avoids the problem altogether by limiting himself to the expression “equality with God,” which he interprets absolutely; Bonnie Bowman Thurston simply translates “essence” without comment (Bonnie Bowman Thurston and Judith M. Ryan, Philippians and Philemon [Sacra Pagina 10; Collegeville, MN: Liturgical Press, 2005]). – Paul Holloway, Philippians (Hermeneia), pp. 117-18

…The first thing to note is that, regardless of which way one understands “equality with God,” it must be taken in a qualified sense, since even in 2:9-11 Christ’s glory still serves the “glory of God the Father” (cf. 1 Cor 15:28). Strictly speaking, Christ is not “equal to God” either before his metamorphosis or after his exaltation. To interpret “equality with God” sensu stricto is therefore not an option. – ibid, p. 120

If Paul had meant “nature” or “essence” then there were other words he would have used such as ** you do not have permission to see this link ** as he does in Rom. 1:20.

Philo of Alexandria says something similar in Embassy to Gaius 110:

Is it fitting now to compare with these oracles of Apollo the ill-omened warning of Gaius, by means of which poverty, and dishonour, and banishment, and death were given premature notice of to all those who were in power and authority in any part of the world? What connexion or resemblance was there between him and Apollo, when he never paid any attention to any ties of kindred or friendship? Let him cease, then, this pretended Apollo, from imitating that real healer of mankind, for the form (μορφὴ) of God is not a thing which is capable of being imitated by an inferior one, as good money is imitated by bad.

But if you pay attention to the previous context in ** you do not have permission to see this link **.

Embassy To Gaius

80
And he looked upon himself as being in this respect superior to all of these beings, because each of them while he had his own peculiar honours had no claim to those which belonged to the others, but he in his envious ambition appropriated all the honours of the whole body of demigods at once, or I should rather say, appropriated the demigods themselves; transforming himself not into the triple-bodied Geryon, so as to attract all beholders by the multitude of his bodies; but, what was the most extraordinary thing of all, changing and transforming the essence of one body into every variety of form (μορφάς morphḗ) and figure, like the Egyptian Proteus, whom Homer has represented as being susceptible of every variety of transformation, into all the elements, and into the animals, and plants, which belong to the different Elements.{5}{the passage in Homer is to be found at Odyssey 4.363. It is imitated more concisely by Virgil, Georg. 4.410, who makes Cyrene tell Aristaeus (which is thus translated by Pope)–“Instant he wears, elusive of the rape, / The mimic force of every savage shape: / Or glides with liquid lapse a murm’ring stream, / Or wrapt in flame, he glows at every limb. / Yet still retentive, with redoubled might / Thro’ each vain passive form constrains his flight. / But when, his native shape resumed, he stands / Patient of conquest, and your cause demands; / The cause that urg’d the bold attempt declare, / And soothe the vanquish’d with a victor’s prayer. / The bands relaxed, implore the seer to say / What godhead interdicts the wat’ry way.”}

114
Have we not, then, learned from all these instances, that Gaius ought not to be likened to any god, and not even to any demi-god, inasmuch as he has neither the same nature (φύσεως phýsis), nor the same essence (ουσίας ousía), nor even the same wishes and intentions as any one of them; but appetite as it seems is a blind thing, and especially so when it takes to itself vain-gloriousness and ambition in conjunction with the greatest power, by which we who were previously unfortunate are utterly destroyed,

210-211
for all men are eager to preserve their own customs and laws, and the Jewish nation above all others; for looking upon their laws as oracles directly given to them by God himself, and having been instructed in this doctrine from their very earliest infancy they bear in their souls the images of the commandments contained in these laws as sacred; (211) and secondly, as they continually behold the visible shapes and forms (μορφάς morphḗ) of them, they admire and venerate them in their minds and they admit such foreigners as are disposed to honour and worship them,

290
O my lord and master, Gaius! this temple has never, from the time of its original foundation until now, admitted any form (μορφήν morphḗ) made by hands, because it has been the abode of God. Now, pictures and images are only imitations of those gods who are perceptible to the outward senses; but it was not considered by our ancestors to be consistent with the reverence due to God to make any image or representation of the invisible God.

299
“Moreover, I have it in my power to relate one act of ambition on his part, though I suffered an infinite number of evils when he was alive; but nevertheless the truth is considered dear, and much to be honoured by you. Pilate was one of the emperor’s lieutenants, having been appointed governor of Judaea. He, not more with the object of doing honour to Tiberius than with that of vexing the multitude, dedicated some gilt shields in the palace of Herod, in the holy city; which had no form (μορφήν morphḗ) nor any other forbidden thing represented on them except some necessary inscription, which mentioned these two facts, the name of the person who had placed them there, and the person in whose honour they were so placed there.

346
So great therefore was his inequality of temper towards every one, and most especially towards the nation of the Jews to which he was most bitterly hostile, and accordingly beginning in Alexandria he took from them all their synagogues there, and in the other cities, and filled them all with images and statues of his own form (μορφής morphḗ)

367
And he took compassion on us, and turned his mind to pity. And he becoming pacified merely said, “These men do not appear to me to be wicked so much as unfortunate and foolish, in not believing that I have been endowed with the nature (φύσιν physin) of God;”

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