The heart of the slave of Allah becomes dried whenever it is devoid of:
- Love for Allah
- Knowledge about Him
- His remembrance (dhikr)
- Supplication and invocation
- Most importantly, Tawhid
This is because the heart of desire (nafs) and the fires of lust infiltrating the heart cause the branches (limbs) to become unresponsive, inflexible and inert (whenever the slave of Allah intends to employ them in good deeds). Under these circumstances, the tree including its branches is rendered useless; its only fitting use as fuel for (Hell) fire.
Allah said, “Then woe unto those who hearts are hardened against remembrance of Allah. Such are in plain error” (Surah al-Zumar 39:22)
When the heart is watered with the rains of Mercy, the branches will be soft, moist, pliable and responsive; if you call them for the worship of Allah, they submit and hasten to obey, letting you reap from each branch the fruits of (true) enslavement to Allah, whose essence is the irrigation of the heart, which influences (the functioning of) the heart and the limbs. On the other hand, when the heart is parched and dried (rigid and hardened), the branches do not perform any good deeds because the essence of life is missing from the heart, thus the limbs are cut off from life accordingly. And even though each limb has been created and prepared to render a unique act of worship demonstrating an aspect of mankind’s servitude to Allah, the limbs cannot produce their anticipated harvest due to incapacity and hinderance in their functioning.
Inner Dimensions of the Prayer Ibn Qayyim Al-Jawziyyah Pages 20-21