Imam as-Sadiq (‘a) said: "My father said to me about his father (‘a) that a man from Kufah wrote to his father viz. to al-Husayn-ibn-’Ali (‘a) asking him (‘a) to imform him of the good of this world and that of the next. Then, he (‘a) wrote (in his reply): 'In the Name Allah the Beneficent, the Merciful'. After that: 'Verily, he who seeks the pleasure of Allah even while displeasing people, He suffices him in his affairs with people. But, he who seeks the pleasure of people while Allah is displeased, he leaves him to people (and he will be far from His Grace), Wassalam'."
Bihar-ul-Anwar, vol. 71, p. 208
Imam ‘Ali ibn Husayn (‘a) said: "He who acts according to what Allah has enjoined for him, is of the best people."
Al-Kafi, vol. 2, p. 81
Imam as-Sadiq (‘a) said: "The one who loves for Allah, hates for Allah, and donates (things) for Allah, thus he is one of those whose Faith is complete."
Al-Kafi, vol. 2, p. 124
Imam Hasan al-’Askari, the eleventh Imam, (‘a) said: "There are no qualities above these two: Faith in Allah and being beneficial to Muslims."
Bihar-ul-Anwar, vol. 17, p.218