رَبَّنَا آمَنَّا فَاغْفِرْ لَنَا وَارْحَمْنَا وَأَنتَ خَيْرُ الرَّاحِمِينَ

Rabbanaa aamannaa fagh-fir lanaa war-hamnaa wa anta Khayrur-raahimiin. (23:109)

Our Lord, we believe, so forgive us, and have mercy on us. You are the Best One to show mercy.

Ameen

The Qur’an mentions this as the du’aa of the people who were ridiculed in this world by the unbelievers. In a glimpse of the Hereafter in the verses just preceding this we see the ridiculers futilely pleading that they be given another chance, while Allah Ta’aala says this regarding those making this du’aa: “I have rewarded them today for how patient they have been: they are the ones who are triumphant” (Al-Mu’minoon 23:111).

When the going gets tough because of peer pressure, powerful media, or the campaigns of the world powers against them, the believers can get a lot of relief through this du’aa.

(Source: Khalid Baig’s commentary to du’aa #26 in the Accepted Whispers: Munajat-e-Maqbul)