1. Paul was concerned about the corporate testimony of the church at Philippi.  Their witness was beginning to be hurt by their selfishness and pride, and conversely their lack of humility, and was leading to disunity. 

2.  Paul encourages them toward humility (the attitude of Jesus) by reminding them that God would enable (energize) them toward right desires and right actions.  He would give them the power to carry out His will for them.

3.  God energizes us and our witness through the Word of God (1 Thes 2:13; 2 Peter 1:3ff).

4.  Instead of relying upon God and His power, they were grumbling and disputing with each other.  While they were to be lights to the world, they were acting more like the darkness around them.