Surah: 107 Al-Maun
This is a Makki Surah and draws its name from its focus on small voluntary actions of goodness. Belief in the Day of Resurrection is essential to maintain the sincerity in believers, as Islam is not restricted to mere rites of worship but a complete system that extends to supporting the entire community.
In this surah, Allaah (SWT) mentions and curses those performers of prayers who do not urge upon feeding the poor, or caring for the orphans, for quite likely they are heedless in their prayers and want to show-off among others. The closer one gets to Allaah (SWT), the more he should render himself in the service of the people.