بسم الله الرحمن الرحيم
Ibn Al-Qayyim – rahimahu Allah – said:
Likewise, from among the causes that alleviate the chest is continually making thikr of Him in every condition [that one is in] and in every place. Because thikr has an amazing effect in alleviating the chest and bringing bliss to the heart. [Whereas] heedlessness [from making rememberance of Him] has a shocking effect in constraining, restricting and tormenting it.
Likewise, from among them [i.e. the causes that alleviate the chest] is kindness to creation, benefiting them with what is possible by use of wealth, power, physical support and the various other acts of benevolence.
For indeed the generous and benevolent individual has the most alleviated of chests, the best spirit and having the greatest peace of mind.
However, the stingy one who has no [characteristic of] benevolence in him, he has the most constricted of chests among humankind, living the bitterest of life and being the saddest and most distressed out of them.
Indeed Allah’s Messenger ﷺ gave an example in the Saheeh of the stingy person and the charitable person:
“Like that of two men wearing metal armour. Whenever the charitable one intends on giving charity, [the armour] widens and expands for him, so much so that it causes his garments to trail and obliterates his traces. But, when the stingy one intends on giving in charity, every ring grips the place where it is and doesn’t expand for him.”
Therefore, this is the example of the alleviation of the charitable believer’s chest and expansion of his heart. [As well as] an example of the one stingy one who has a constrained chest and a heavy heart.
Source: Ibn Al-Qayyim, Zaad Al-Ma’aad, Chapter: Concerning the causes of alleviating the chest, [of which] complete and perfect acquisition belongs to him [i.e. the Messenger] ﷺ