|Reported by Abu Hurairah (r) that Muhammad (S) said: “One who covers up the failings of somebody in this world, will have his shortcomings covered up by God on the Day of Judgment.” (Muslim)
Transliteration: “La Yasturu ‘Abdun ‘Abdan Fid Dunya Illa Satarahullahu Yawmal Qiyamah.”
The concept expressed by the phrase “To err is human” is fundamental to the Islamic conception of human personality. God does not expect us to be free of errors or sins, although He does want us to try our best to avoid them. When we fail, He wants us to sincerely repent and seek forgiveness. Indeed, He is the most-Forgiving, the most-Compassionate.
As we all want God to be lenient to us, we need to be lenient to others. As we desire from God that He covers us – particularly on the Day of Judgment – we can easily attain such protection by covering the weaknesses of others.
The matter of concealing the faults of others is mentioned in numerous hadith of Muhammad (S). In particular, we find the following: “O gathering who believe with their tongues but faith has yet to enter into their hearts, do not backbite the Muslims. And do not search into their private matters. Whoever searches for their private matters will have Allah follow up his private matters. And whose private matters Allah follows, He will expose him even [if his act were done] in his house.” [Ahmad and Abu Dawood]