TABARANI 13783:
from ʿAbdullāh b. ʿAmr —
[Machine] The Messenger of Allah ﷺ said, "There is no remembrance better than La ilaha illa Allah (there is no god but Allah) and no supplication better than istighfar (seeking forgiveness)." Then the Messenger of Allah recited, "So know, [O Muhammad], that there is no deity except Allah and ask forgiveness for your sin and for the believing men and believing women."
الطبراني ١٣٧٨٣:
عن عبد الله بن عمرو —
قَالَ رَسُولُ اللهِ عَلَيْهِ وَسَلَّمَ «مَا مِنَ الذِّكْرِ أَفْضَلُ مِنْ لَا إِلَهَ إِلَّا اللهُ وَلَا مِنَ الدُّعَاءِ أَفْضَلُ مِنَ الِاسْتِغْفَارِ» ثُمَّ تَلَا رَسُولُ اللهِ ﷺ {فَاعْلَمْ أَنَّهُ لَا إِلَهَ إِلَّا اللهُ وَاسْتَغْفِرْ لِذَنْبِكَ وَلِلْمُؤْمِنِينَ وَالْمُؤْمِنَاتِ}
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