The servant (who conceals) the faults of others in this world, Allah would conceal his faults on the Day of Resurrection. (Using translation from Muslim 2590b)

عَنِ النَّبِيِّ ﷺ أَنَّهُ قَالَ لَا يَسْتُرُ عَبْدٌ عَبْدًا فِي الدُّنْيَا إِلَّا سَتَرَهُ اللهُ يَوْمَ الْقِيَامَةِ