Do good for the sake of your Lord alone and never expect anything in return

In the Holy Quran we are told: 

     "(The righteous are those) who feed the poor, the orphan 
     and the captive for the love of Allah, saying: 'We feed you 
     for the sake of Allah alone, we seek from you neither 
     reward nor thanks.'" [Sura Al-Insan 76:8-9]