Imam Ali(as) advised Kumayl Ibn Ziyad Nakha'i to recite this "Du'a" on the eve of (i.e. evening preceding) every Friday, or once a month or at least once in every year so that, added Imam Ali(AS), "Allah may protect thee from the evils of the enemies and the plots contrived by impostors. O' Kumayl! in consideration of thy companionship and understanding, I grant thee this honour of entrusting this "Du'a" to thee."