“Who is he that will lend to Allah a goodly loan so that He may multiply it to him many times? And it is Allah that decreases or increases (your provisions), and unto Him you shall return.”
[Surah al-Baqarah: 245]

“The likeness of those who spend their wealth in the Way of Allah, is as the likeness of a grain (of corn); it grows seven ears, and each ear has a hundred grains. Allah gives manifold increase to whom He wills. And Allah is All-Sufficient for His creatures’ needs, All-Knower.”
[Surah al-Baqarah: 261]