Be aware, be warned, and be exhorted that, if we have any desire to overcome faults, if we sincerely desire to be in God's Kingdom, if we desire to be like God and glorify Him, we need to protect our relationship with Him. He is the Source of the power to do all things, even to grow while also enduring these intense times. Paul is saying that he knows how to discipline himself and thus keep on track in every circumstance of life. By this time in Paul's life, he had the skills required for making the best of every situation.
He is not suggesting that he did this alone through mere human discipline and skill that anybody can achieve, but that he was enabled because of his faithful relationship with Christ. The real dynamic is that Christ has the power, and it was He who faithfully enabled Paul. The apostle's skills, which enabled him to accomplish things that pleased God, were spiritual.
John W. Ritenbaugh
Power Belongs to God (Part One)
Paul demonstrates the proper attitude to have: He was content whether poor or prosperous, whether weak or strong, whether people loved him or hated him. It is not easy to do sometimes, but he says, "Whatever state I'm in, I'm going to be content because, when I have Christ in me, I can do anything that He wants me to do. So I can't think about those other things. I have to be content with what God has given."
A person's condition or his position does not need to matter a whit as long as Christ is working through him.
Richard T. Ritenbaugh
Frustration and bitterness were not Paul's companions. He did not make what he considered to be his needs absolutes in order to determine his sense of well-being. By faith, he believed that God was watching over his life and would provide.
Paul followed the example of Jesus Christ, and this is the example that we too are to follow. We are to learn to be angry and not sin. We are to learn not to make frustration, bitterness, and hostility regular parts of our lives.
John W. Ritenbaugh
The Spiritual Mark of the Beast
Other Forerunner Commentary entries containing Philippians 4:12: