Abdullah bin Samit reported,

Ali reported that he was with Abu Dharr when his stipend came, and a slave girl of his was with him. She began to take care of his needs, and seven coins were left over with her. He instructed her to buy copper coins with them.I said to him, "Why not save it for a need that may befall you, or for a guest who comes to stay with you?"He replied, "My dear friend ﷺ charged me that any gold or silver tied up in a purse is a burning ember upon its owner until he spends it in the path of Allah ."

عن عبد الله بن الصامت

أنه كان مع أبي ذر، فخرج عطاؤه ومعه جارية له، فجعلت تقضي حوائجه، قال: ففضل معها سبع، قال: فأمرها أن تشتري به فلوسا، قال: قلت له: لو ادخرته للحاجة تنوبك، أو للضيف ينزل بك. قال: إن خليلي عهد إلي: أن أيما ذهب أو فضة أوكي عليه، فهو جمر على صاحبه حتى يفرغه في سبيل الله عز وجل.