Abu Hurairah (Radhiallaho anha) reported:
The Prophet (Sallallaahu 'alaihi wasallam) said,
"Whosoever performs Qiyam during Lailat-ul-Qadr (Night of Decree), with Faith and being hopeful of Allah's reward, will have his former sins forgiven.''
[Al-Bukhari and Muslim]
Commentary:
Qiyam here means what keeps one awake to one's capacity and for worship and makes one perform Nawafil, impels one to beg pardon for sins from Allah, urges one to praise Him. Specially, if a person performs `Isha prayer and Fajr prayer in congregation, he will hopefully attain all those distinctions which are mentioned in this Hadith.