Recognizing God's sovereignty in his circumstance, Paul viewed himself primarily as a prisoner of the Lord, not as a prisoner of Rome. Thus, he must have reasoned that since he was incarcerated, it was because God wanted the people around him to hear the Gospel. He had the choice of either telling them his own bad news through complaining or telling them God's good news through evangelism. Paul chose the latter, in part because he discovered an important key to victorious living. Most people think they will stop complaining when they finally get happy. Paul indicates that people will get happy when they finally stop complaining! The difference is profound.
Paul implies in Philippians 2:14-16 that complaining Christians look and sound like the depraved generation of which they are a part! That's a serious charge, but the stakes are high. What unbeliever would want to accept Christ into his life if Christ apparently made no difference in the life of a Christian?
Walk it off!
Paul's admonition to avoid complaining is rooted in his understanding of the Old Testament. One of the saddest cases of God's people complaining is recorded in Numbers 14, where God said to those who complained: "Your carcasses shall fall in this wilderness. ... Doubtless ye shall not come into the land."
What a tragedy! Israel complained about their leaders, their food supply, and the difficult challenge to occupy Canaan. God was fed up with such relentless carping. In fact, according to Deuteronomy 1:2, it should have taken the Israelites less than two weeks to travel from where they had received the Ten Commandments to the edge of the Promised Land. As it turned out, their trip took forty years. It was God's way of telling them to "walk it off"!
The end result was that many died in the wilderness and thereby were denied entrance into the land. Why such a harsh judgment? From God's perspective, to complain is to doubt His promises and provisions. To complain is to slander His sovereignty and assault His lordship. To complain is to accuse God of being a bad Father!