In The Name of Allah, the Most Merciful, The Bestower of Mercy.

Allah, The Most High, said:

يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓاْ أَنفِقُواْ مِن طَيِّبَـٰتِ مَا ڪَسَبۡتُمۡ وَمِمَّآ أَخۡرَجۡنَا لَكُم مِّنَ ٱلۡأَرۡضِ‌ۖ وَلَا تَيَمَّمُواْ ٱلۡخَبِيثَ مِنۡهُ تُنفِقُونَ وَلَسۡتُم بِـَٔاخِذِيهِ إِلَّآ أَن تُغۡمِضُواْ فِيهِ‌ۚ وَٱعۡلَمُوٓاْ أَنَّ ٱللَّهَ غَنِىٌّ حَمِيدٌ
ٱلشَّيۡطَـٰنُ يَعِدُكُمُ ٱلۡفَقۡرَ وَيَأۡمُرُڪُم بِٱلۡفَحۡشَآءِ‌ۖ وَٱللَّهُ يَعِدُكُم مَّغۡفِرَةً۬ مِّنۡهُ وَفَضۡلاً۬‌ۗ وَٱللَّهُ وَٲسِعٌ عَلِيمٌ۬

O you who believe! Spend of the good things which you have (legally) earned, and of that which We have produced from the earth for you, and do not aim at that which is bad to spend from it, (though) you would not accept it save if you close your eyes and tolerate therein. And know that Allah is Rich (Free of all wants), and Worthy of all praise. Shaitan (Satan) threatens you with poverty and orders you to commit Fahsha (evil deeds, illegal sexual intercourse, sins etc.); whereas Allah promises you Forgiveness from Himself and Bounty, and Allah is All-Sufficient for His creatures’ needs, All-Knower. [Al-Baqarah. 267-268]

Imam As-Sadi, may Allah have mercy upon him, said:

Allah commands His believing servants to spend from the good things He has facilitated for them and from that which He has provided for them from the earth. Just as Allah bestowed on you by making it easy for you to acquire these things, you should spend from it as an act of gratitude to Allah, fulfilling some of the rights owed to your breathen in faith and as a means of purifying your wealth. The goal behind this spending is that you give the good things which you love for yourselves, and not the bad which you neither want, nor accept, except with closed eyes (reluctance).

وَٱعۡلَمُوٓاْ أَنَّ ٱللَّهَ غَنِىٌّ حَمِيدٌ

And know that Allah is Rich (Free of all wants), and Worthy of all praise.

Meaning: Allah is absolutely not in need of you. The benefit of your charity and deeds returns (only) to you. Alongside the fact that Allah is the only one worthy of all praise, He praises you for fulfilling the praiseworthy deeds and upright characteristics which He has commanded you, therefore it is obligated to you to fulfil His commands because it is means of strengthening your hearts- a means of piety and delight for the souls.

And beware of following your enemy the Shaytan, who commands you to refrain from spending your wealth- frightens you with poverty and neediness when you are required to spend. This is not sincere advice, but rather it is deception at the highest level.

إِنَّمَا يَدۡعُواْ حِزۡبَهُ ۥ لِيَكُونُواْ مِنۡ أَصۡحَـٰبِ ٱلسَّعِيرِ

He only invites his Hizb (followers) that they may become the dwellers of the blazing Fire.

An Excerpt from Tafseer as-Sadi