The Last Third Of The Night
Abu Hurairah (radiAllahu anhu) narrated that Allah’s Messenger (salAllahu alayhi wasalam) said: ‘In the last third of every night our Rabb (Cherisher and Sustainer) (Allah (Subhanahu wa Ta’ala)) descends to the lowermost heaven and says; “Who is calling Me, so that I may answer him? Who is asking Me so that may I grant him? Who is seeking forgiveness from Me so that I may forgive him?.”‘ [Sahih al-Bukhari, Hadith Qudsi]
Amr ibn Absah narrated that the Prophet said: ‘The closest any worshipper can be to His Lord is during the last part of the night, so if you can be amongst those who remember Allah at that time, then do so.’ [at-Tirmidhi, an-Nasa'i, al-Hakim - Sahih]