A man is the one who fears the death of his heart, not his body.
— Imam Ibn Qayyim رحمه الله
Source: Madarij Al-Salikeen 3/248
The Five Levels of Performance in Prayer (Salah)
And mankind, with regard to their performance of prayer (salah) [or namaaz] are in five levels. First The level of the one who is negligent and wrongs his soul: He is the one who falls short in performing wudoo properly, performing the prayer upon its time and within its specified …