In his book Hilyat al-Abdaal, Ibn Arabi mentions that there are four cornerstones to the spiritual path: Seclusion, Silence, Hunger, and Wakefulness.

In his book Asraar al-Siyam (The Secrets of Fasting), the Azhari imam, Shaykh Saleh al-Jaafari, writes:

“They have mentioned that the Abdaal have four characteristics: Silence, Hunger, Seclusion, and Wakefulness. Now Silence is brought about by Hunger, and so is Wakefulness. And what remains is Seclusion, which is its fruit, because it is brought about by the lights of dhikr, for they cause one to find intimacy and comfort in the company of Allah (al-uns billah) and alienation in the company of all other than Him (al-wahsha ‘an siwah).

So Hunger is the basis for the (other) three, and it happens while Fasting.”