Charity does not decrease wealth

Narrated Abu Huraira:

Allah's Messenger (sallallaahu alayhi wa sallam) said, "Allah said, 'O son of Adam! Spend, and I shall spend on you."

Sahīh al-Bukhāri Hadīth No. 5352

Abu Huraira reported Allah's Messenger (sallallaahu alayhi wa sallam) as saying:

Charity does not in any way decrease the wealth and the servant who forgives Allah adds to his respect, and the one who shows humility Allah elevates him in the estimation (of the people).

Sahīh Muslim Hadīth No. 2588

Sheikh Khālid bin Uthmān al-Sabt said:

وكثير من الناس يظن أنه إذا أنفق نقص ماله، وهذا غير صحيح، إذا أنفق الإنسان في الوجوه الصحيحة من الواجبات والمستحبات فإن ذلك يكون سبباً لرزق يسوقه الله  إليه

Many people think that when one spends (in charity) his wealth will decrease. This is incorrect. When a person spends by giving obligatory charity (such as Zakāh) and optional charity, then that becomes a cause for rizq which Allāh gives the person.