Long ago, a King was Hunting a deer in a Jungle with his ministers.  While hunting near a bush he was bitten by a snake on his leg thumb. King shouted aloud and was Unconscious.   He was then taken to his palace and as per the advice of the doctor he has to remove leg thumb (as it was fully poisoned) and as per the Ministers decision to save the life of King first.  

Doctor operated the leg thumb and removed it.  When the King came to his conscious found he has no leg thumb.  He called his Ministers and asked, "Who has removed my leg thumb?"  Doctor was pointed at this Juncture.  King immediately ordered his Minsters to put the Doctor behind the Bars (Jail).  Months passed. 

When the King was normal by Health, he again started Hunting for deer a in Jungle hiding behind the tree. This time, some Jungle people wanted to give a Bali to their Mountain God.  The King was trapped and carried by them.  Before offering the King to the God  they removed all the Jewels & ornaments and with milk and turmeric bath he was taken to the Pujaari (the Priest).  Pujari found that the leg thumb of King was missing.  Hence such,  "Disabled person cannot be given as Bali to God and relieved him back to his Palace.  King said to himself, "Thank God, my leg thumb was removed by Doctor and hence my life was saved today." After reaching Palace King ordered his minister to bring Doctor in front of Him. So the Doctor was in chain brought from the Jail/Prison.  King bowed to the feet of the Doctor and said, "Today my life was saved, Thank you for cutting my toe thumb."  And Doctor was relieved  from the Prison by order.  

Immediate, Doctor fell on the feet of the King and bowed and said, "I should be thankful to you."  Kind said, " But why ?" Doctor said, "If you would have put me in Prison / Jail, I would have accompanied you to Jungle. Those people who relieved you,  would have caught me in place of you and I would be a Bali to God Mountain.  

Moral: What happened and what is happening is already planed by God.