Likewise, from among them [i.e. the causes that alleviate the chest] is leaving off excessive looking, speech, listening, eating and sleep. For indeed too much of these turns into pain, sadness and grief within the heart. They confine it, constrain it and cause it to become tightened. It [i.e. the heart] agonizes because of them, in fact the vast majority of agonies in this world and the next are due to them.
So la ilaa-ha illa Allah! How constrained is the chest of he who took an active part in every affliction from these affliction! How bitter is his life! How bad is his condition! How severe is the heaviness of his heart.
Likewise, laa ilaa-ha illa Allah! How blissful is the life of he who took an active part in [attaining] every characteristic from those praiseworthy characteristics. His efforts would revolve around them, being committed to them.
Therefore, this person will have an abundant portion of what is mentioned in the statement of Allah – The Most High:
﴿إنَّ الأَبْرَارَ لَفِى نَعِيم﴾ [الانفطار: 13]
Indeed the righteous shall surely be in bliss [Al-Infitaar: 13]
Whereas the former person [i.e. the wretched one] will have an abundant portion of what is mentioned in the statement of Allah – The Most High:
﴿وإنَّ الفُجَّارَ لَفِى جَحِيمٍ﴾ [الانفطار: 14]
And indeed the sinners shall surely be in the Hellfire [Al-Infitaar: 14]
The point of all this is that Allah’s Messenger ﷺ was the most perfect of creation in respect to every characteristic by which relaxation of the chest, lightheartedness, delight of the eye and life of the soul can be attained.
Therefore, he is the most perfect of creation in relation to this relaxation, life and delight of the eye alongside what he has been specified with of perceivable relaxation.
He is the most perfect of creation in respect to being followed. The most perfect in relaxation, joy and delight of the eye, and in accordance to the degree that he [i.e. The Messenger] is followed, does the slave attain whatever he actually ends up attaining of relaxation of the heart, delight of the eye and joy of the soul.
Therefore he ﷺ is at the peak of perfection in relation to relaxation of the chest, elevation of rank and pardoning of sin. And his followers have such a portion of that that is proportionate to the degree that they follow him. And Allah is the one from whom aid is sought.
Similarly, his followers have such a portion of protection from Allah for them, safeguarding them, defending them, strengthening them and aiding them that is proportionate to the degree of their following [The Messenger]. [So among them is] the one who gives it little care, and [among them] is he who gives it a great deal of importance.
Therefore, whosoever ends up finding goodness let him praise Allah. And whosoever ends up finding other than that, then he can blame none but himself.
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