once
وَقَالَ صلى الله عليه وسلم: ((أَقْرَبُ مَا يَكُونُ الرَّبُّ مِنَ الْعَبْدِ فِي جَوْفِ اللَّيْلِ الآخِرِ فَإِنِ اسْتَطَعْتَ أَنْ تَكُونَ مِمَّنْ يَذْكُرُ اللَّهَ فِي تِلْكَ السَّاعَةِ فَكُنْ)).
Meaning
He said: ‘The nearest the Lord comes to His servant is in the middle of the night, so if you are able to be of those who remember Allah at that time, then be so.
Source and references
Hisn al-Muslim, entry 251.The reference is copied from the edition; separate editorial verification is not complete yet.
Source edition: Fortress of the Muslim. Open source ↗