The Holy Prophet [s] said: "The honour of a believer lies in his vigilance at night and his esteem lies in his autonomy from people."
Bihar-ul-Anwar, vol. 77, p. 20
Imam Amir ul Mu'mineen Ali [a] said: "He who sleeps too much at night, will lose something of his deeds (i.e., night prayers) which he cannot gain during the day-time."
Imam Sadiq [a] said that Allah (s.w.t.) in a revelation told Moses, the son of 'Imran [a]: "O' you son of 'Imran! Those who only claim that they love Me, tell a lie, for when the night falls they neglect Me."
Bihar-uI-Anwar, vol. 13, p. 329
Imam Sadiq [a] said: "Never miss midnight prayers, because, in fact, the real loser is he who misses (the advantage of) the midnight prayer."
Bihar-ul-Anwar, vol. 83, p. 127
Imam Sadiq [a] said: "The Messenger of Allah [s] told Gabriel to preach to him, and he said: 'Live howsoever you like but you will surely die; love whatsoever you like but you will surely depart from it; do whatsoever you like but you will certainly meet it (and receive its reward). The honour of a (Muslim) believer is his midnight prayers, and his nobility is his refraining from (ruining) people's reputation"
Khisal by Saduq, p. 7
Imam Sadiq [a] said: "There are three things which are the honour of a believer and his ornament both in this world and the next. They are: prayers in the last part of night (night prayers), not coveting what people possess in their hands, and the love (and leadership) of an Imam from the progeny of Muhammad [s]."
Bihar-ul-Anwar, vol. 75, p. 107
Imam Muhammad-ibn-Ali, Jawad-ul-'A'immah, [a] said: "He who has confidence in Allah, sees joy; and he who trusts on Him, He will suffice his affairs."
Bihar-ul-Anwar, vol. 78, p. 79