Is there any evidence that μορφῇ θεοῦ (morphe theou) in Philippians 2:6 means the "nature" of God the Father? Is there a NT evidence and contemporary first century evidence that morphe is used as having the meaning of "nature?"
Jesus was both "in the form of God" (ἐν μορφῇ θεοῦ) and "took the form of a servant" (μορφὴν δούλου λαβών).
form of a servant: servant :: form of God: ___
form of X: X :: form of Y: Y
The word μορφῇ means "form, outward appearance, [or] shape"1 (occurring in the dative in this context following the preposition ἐν). To be very blunt, translating this as "nature" (as the NIV does) is a poor translation choice. Discussion of God's nature is theologically charged and thus using "nature" in this context could be misleading. The NET translators explain the usage of μορφῇ in Philippians 2:6 by saying:
The next verse uses the same word (but in the accusative) in the phrase μορφὴν δούλου λαβών ("taking [the] form of a slave"). Jesus truly was God, and also he truly was a servant. For an in depth understanding of the usage of μορφῇ both in biblical and extra-biblical writings I have copied a lexical entry for you:
Concerning the usage of μορφή in both passages, in v. 6 "being" (ὑπάρχων) in the form of God was natural (he was 'in the form of God'), while in v. 7 'taking' (λαβών) the form of a slave was an active choice.
1 William Arndt, Frederick W. Danker and Walter Bauer, A Greek-English Lexicon of the New Testament and Other Early Christian Literature, 3rd ed. (Chicago: University of Chicago Press, 2000), 659.
2 Biblical Studies Press, The NET Bible First Edition Notes (Biblical Studies Press, 2006), Php 2:6.
3 Arndt, Danker, and Bauer, 659.
The occurrence of morphe and its co-words in the New Testament proves that it denotes " nature" not just mere appearance:
Moral nature Romans 12:2 ( are we to change in "appearance' only as Christians and not in our moral nature? also 2 Corinthians 3:18 ) Servant's nature Philippians 2:7 ( did he just "appeared" to be a servant or really become a servant?) God's nature Philippians 2:6 ( Even though if it means "appearance" here it still requires that he has the Father's nature because only the Father has a divine appearance. Check below)
"Son of Man" Daniel 7:13
"Son of Man" Revelation 1:13
"The hair of his head was pure like wool" Daniel 7:9
"The hairs of his head were white like wool, as white as snow" Revelation 1:14
"A Man clothed in Linen" Daniel 10:5
"A Man clothed with a Long Robe" Revelation 1:13
"With a belt of fine Gold" Daniel 10:5
"With a golden sash" Revelation 1:13
"His face like the appearance of lightning" Daniel 10:6
"His face was shining like the sun shining in full strength" Revelation 1:16
"His eyes like flaming torches" Daniel 10:6
"His eyes were like a flame of fire" Revelation 1:14
"His arms and legs like the gleam of burnished bronze: Daniel 10:6
"His feet were like burnished bronze, refined in a furnace" Revelation 1:15
"The sound of his words like the sound of a multitude", Daniel 10:6
"His voice was like the roar of many waters" Revelation 1:15
"I fell on my face in deep sleep with my face to the ground" Daniel 10:9
"When I say him I fell at his feet as though dead" Revelation 1:17
"And behold a hand touched me and set me trembling on my hands and knees" Daniel 10: 10
"But he laid his right hand on me…" Revelation 1:17
"Then he said to me, Fear not" Daniel 10: 12
"…Saying, Fear not" Revelation 1:17