Mujahid reported: Ibn Abbas, may Allah be please with him, said, “Mention your brother when he is absent in the way you would love to be mentioned by him. Forgive him as you would love to be forgiven by him.”
Source: al-Ṣamt li-Ibn Abī Dunyā 114
عَنْ مُجَاهِدٍ عَنِ ابْنِ عَبَّاسٍ رَضِيَ اللَّهُ عَنْهُمَا قَالَ وَاذْكُرْ أَخَاكَ إِذَا تَغَيَّبَ عَنْكَ مِمَّا تُحِبُّ أَنْ يَذْكُرَكَ بِهِ وَاعْفِهِ عَمَّا تُحِبُّ أَنْ يُعْفِيكَ مِنْهُ
114 الصمت لابن أبي الدنيا