5 Let this mind be in you, which was also in Christ Jesus:
So it's talking about a mind, not a nature, not a physical essence, not a Divine substance, but a mind. A mind.
Christ gave the ultimate example of humility when he said to his Father, 'Not my will, but Thine, be done.'
Despite the fact that Christ manifested the character of God perfectly, so that whosoever saw Christ saw God (which is precisely what is required of us, but we never manage it perfectly), Christ still did not consider it appropriate to seize at equality with God (which tells us that he never was equal with God), but rather, subjected himself as a servant.
Despite a life of perfect obedience, manifesting the character of God perfectly , Christ did not demand salvation on the basis of works - he knew that salvation cannot be 'earned' in that sense.
Rather, he submitted himself to the will of his Father and God, being an example to us, that we might do the same.
1I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service.
2And be not conformed [or 'absorbed', given the passive mood of the verb] to this world: but be ye transformed [the word is 'metamorphow' by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.
- We are to live our lives as sacrifices to God, as Christ did.
- We are not to be passively absorbed by the world, that we might look like them.
- We are to present ourselves as reflections of the Divine character, change our appearance (metamorphe - clearly nothing to do with rank here), so that when others look on us, they see God (as per Matthew 5:16).
- This is our reasonable service , a life of subjecting our will to the will of God, just as Christ made himself a servant, and subjected himself to the will of God.
The humility here spoken of in Philippians 2 is the humility Christ showed in serving God rather than himself - precisely the same humility we are to show to others:
2 Let every one of us please his neighbour for his good to edification.
3For even Christ pleased not himself; but, as it is written, The reproaches of them that reproached thee fell on me.