Rejoicing is a choice.  We see this in Philippians 4:4. Paul was writing to the Philippians from prison and he tells the Philippians, “Rejoice in the Lord always; again I will say, rejoice.” The Greek word “say,” ero, is in the future tense. The future tense means that Paul was viewing his situation objectively, from the outside looking it. He had given considerable thought as to how he should handle his conundrum and concluded that the best way forward was to praise the Lord for his faithfulness. 

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