Serenity is an ideal that is rare in this hard & stressful world. The best definition is right from Webster as “not disturbed or troubled; calm, peaceful, tranquil, quiet etc.” Easily one could say that Serenity is one of those “Elusive Things” (link 8) this world is good at neutralizing. But nearly all have heard of the “Serenity Prayer”:
     God grant me the serenity to accept the things I cannot change;
         courage to change the things I can; and wisdom to know the difference.
     Living one day at a time; enjoying one moment at a time; accepting hardships as the pathway to peace.
     Taking, as Jesus did, this sinful world as it is, not as I would have it.
     Trusting that He will make all things right, if I surrender to His Will.
     That I may be reasonably happy in this life and supremely happy with Him forever in the next. Amen.
         Reinhold Niebuhr
Now this was written by a liberal Protestant theologian several decades ago.  It contains good points, and misleading ones. That part about “accepting things” and “courage to change” is off base BECAUSE the beauty of true Christianity is that God’s Spirit in our lives gives us the power to change for the better – not just courage to do it ourselves. That approach is condemned in Scripture as salvation by works – Ephesians 2:8-9 (below). Living & Enjoying one day & moment is commendable – too many folks live in the past or in the future. We should live in the present, thinking Godly thoughts Philippians 4:8, and of course pray for our needs – it’s a priceless benefit of Christ’s salvation package. Philippians 4:6.
     “Accepting hardships as the pathway to peace”, speaks of a mysterious Divine principle we see in 2 Corinthians 12:10 “For the sake of Christ, then, I am content with weaknesses, insults, hardships, persecutions, and calamities; for when I am weak, then I am strong.” Many folks never understand this, but some do – see Psalms 25:14  
     Now when R. Niebuhr says that “Jesus took this sinful world as it is”, he was speaking with a lame liberal forked tongue. J.C. always made an uncompromising stand for truth. He also claimed to be the SOURCE of change & Hope & serenity. John 14:6
     I appreciate Niebuhr’s conclusion “Trusting that He will make all things right if I surrender to His Will.” A more recent theologian said, “The surrender of the will is the key to becoming a Christian, and the secret to living a victorious Christian life.” Bill Bright. That sounds like moving SELF from the throne of one’s life & asking J.C. to be on the throne. It’s only then we can have those BENEFITS – “That I may be reasonably happy in this life and supremely happy with Him forever in the next.” That’s serenity. 

**  Ephesians 2:8-9 – “For by grace you have been saved through faith; and this is not your own doing, it
      is the gift of God – not because of works, lest any man should boast.”
**   Philippians 4:8 – “Finally, brethren, whatever is true, whatever is honorable, whatever is just, 
      whatever is pure, whatever is lovely, whatever is gracious, if there is any excellence, if there is
      anything worthy of praise, think about these things.”
**  Philippians 4:6 – “Have no anxiety about anything, but in everything by prayer and supplication with
     thanksgiving let your requests be made known to God.”
**  Psalms 25:14 KJV – “The secret of the Lord is with them that fear him, and he will shew them his
**  John 14:6 – “Jesus said to him, ‘I am the way, and the truth, and the life; no one comes to the 
      Father, but by me.”
     Choose Jesus, He is alive, and His own gift of serenity can be yours: John 14:27 – “Peace I leave with you; my peace I give to you; not as the world gives do I give to you. Let not your hearts be troubled, neither let them be afraid.”

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