It is recommended to offer a specific prayer on each of the White Nights Ayyam-e-Baydh (i.e. the 13th, 14th, and 15th nights of each Arabic month) in Rajab, Sha’ban, and Ramaḍān. On the 13th night of Rajab (Sha‘bān, Ramaḍān), it is recommended to offer a prayer consisting of two rakat each in which it is recommended to recite Surah al-Fātiḥah once and Surahs Yasin (No. 36), al-Mulk (No. 67), and al-Tawḥīd.

A similar prayer of four rakat (to be recited in 2 rakat each), should be offered on the 14th night. Also, a similar prayer of six rakat (in 2 rakat each), should be offered on the 15th night.

In this respect, Imam Ja’far al-Sadiq (a.s.) is reported as saying, “Whoever offers these prayers, will be awarded the merits of these three months (namely, Rajab, Sha‘bān, Ramaḍān) and will have all his sins forgiven, except polytheism.

The 13th of Rajab (Sha‘bān, Ramaḍān) is the first of the White Days on which it is recommended to observe fasting, according to narrations, so as to earn an abundant reward.

As for those who intend to recite the famous supplication known as Dua Ummi-Dawud, they may begin with observing fasting on this day.

Dua Mujeer is highly recommended to be recited on the 13th, 14th and 15th of Rajab, Shaban and Ramadan