Abu Huraira reported Allah's Messenger (ﷺ) as saying that Allah, the Exalted and Glorious, thus stated:

I live in the thought of My servant as he thinks about Me, and I am with him, as he remembers Me. And if he remembers Me in his heart, I also remember him in My Heart, and if he remembers Me in assembly I remember him in the assembly, better than he (does that), and if he draws near Me by the span of a palm I draw near him by the cubit, and if he draws near Me by the cubit I draw near him by the space (covered by) two hands. And if he walks towards Me, I rush towards him.

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، وَأَبُو كُرَيْبٍ - وَاللَّفْظُ لأَبِي كُرَيْبٍ - قَالاَ حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏

‏ يَقُولُ اللَّهُ عَزَّ وَجَلَّ أَنَا عِنْدَ ظَنِّ عَبْدِي وَأَنَا مَعَهُ حِينَ يَذْكُرُنِي فَإِنْ ذَكَرَنِي فِي نَفْسِهِ ذَكَرْتُهُ فِي نَفْسِي وَإِنْ ذَكَرَنِي فِي مَلإٍ ذَكَرْتُهُ فِي مَلإٍ خَيْرٍ مِنْهُ وَإِنِ اقْتَرَبَ إِلَىَّ شِبْرًا تَقَرَّبْتُ إِلَيْهِ ذِرَاعًا وَإِنِ اقْتَرَبَ إِلَىَّ ذِرَاعًا اقْتَرَبْتُ إِلَيْهِ بَاعًا وَإِنْ أَتَانِي يَمْشِي أَتَيْتُهُ هَرْوَلَةً ‏

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