And they give food in spite of love for it to the needy, the orphan, and the captive, [Saying], 'We feed you only for the countenance of Allah. We wish not from you reward or gratitude.
The example of those who spend their wealth in the cause of Allah is like that of a grain that sprouts seven ears; in each ear is a hundred grains.
And Allah multiplies (the reward) for whom He wills. And Allah is All-Encompassing, All-Knowing.
[Surah Al-Baqarah: 261]
Whoever builds a mosque for the sake of Allah, Allah will build for him a house in Paradise.
(Sahih Muslim: 727)