Generosity stems from confidence in divine reward
Nahj al-Balāgha|Volume 1|Book 3|Chapter 138
١٣٨. وَقَالَ (عليه السلام): مَنْ أَيْقَنَ بِالْخَلَفِ جَادَ بِالْعَطِيَّةِ.
138. Amīr al-mu’minīn, peace be upon him, said: He who is sure of a good return is generous in giving.