" Allah will remove his sins for him as a tree sheds its leaves."

Narrated 'Abdullah bin Mas'ud:

I visited Allah's Apostle (may peace be upon him) while he was suffering from a high fever. I touched him with my hand and said, "O Allah's Apostle (may peace be upon him)! You have a high fever." Allah's Apostle (may peace be upon him) said, "Yes, I have as much fever as two men of you have." I said, "Is it because you will get a double reward?" Allah's Apostle (may peace be upon him) said, "Yes, no Muslim is afflicted with harm because of sickness or some other inconvenience, but that Allah will remove his sins for him as a tree sheds its leaves."

[ Sahih Al Bukhari : Book 70, hadith 564 ]

If Prophet Muhammad ( P.B.U.H ) ..the greatest Messenger and a Prophet of the highest degree can be subjected to such pain and suffering,  who are we to complain?
May be, at least this way our sins are forgiven and we are inclined to seek guidance towards the right path.