This may well be a song or poem which Paul quotes in these verses, but one with vital importance. In most versions, Paul's words are translated as 'Christ EMPTIED Himself'. It reminds us that when Jesus walked this earth, He didn't resort to using His divine powers to bring miraculous healing or supernatural response from His creation, He relied completely on the will of His Father God. The natural tendency, when we read the Gospel accounts, that when Jesus, for example, stilled the storm He was using the 'God' part of Him is shown to be false. Remember the Devil's temptations in the wilderness recorded in Luke 4 v 1-13 ? Well, they were to do with trying to get Jesus to use His spiritual powers in some way or to depend upon His supernatural connections for protection. Jesus chose the hard route, the self-emptying way, to fully understand and empathise with fallen, broken human beings. He said at one point that His followers would be able to do as much as He could and even greater things (John 14 v 12), because they would have the Holy Spirit living in them and if His followers were FULLY obedient to Him they could do as He had done. I've always found this passage absolutely transformational in my thinking and if, understandably, you are concerned that this is a couple of verses and a quote from an ancient hymn at that, then think for a moment. Apply the two options to what you remember of the ministry of Jesus and decide what is right: That Christ retained His full powers as God's Son-where do you see that? In the temptations? On the cross-'If He was the Son of God He would call down angels to rescue Him', the crowd exclaimed (Matthew 27 v 40-43) ? But, if you go along with Christ emptying Himself of His divine powers before He came to be born, doesn't that change your thinking about Jesus? The call from Paul is that we should be like Christ. Not so much in what we do, but the attitude we have: we are to be servants as Jesus was, living for others and not Himself, always doing His Father's will. That is why it is difficult to accept when Christians trumpet their God-given abilities, when they lord it over others, when they become easily dissatisfied when their church leadership do not give them the limelight. We are all called to show our servant-heart!