Ayyam Bayz

13th, 14th and 15th of Rajab, Sha’aban and Ramadhan are known as "Ayyam Bayz" (the days of surpassing splendor). Imam Jafar Sadiq (a.s) had said: Who so prays during the nights of "Ayyam Bayz", in fact, stands at the door of superabundant favors, bounties and benefits available in these months.

1- It is highly desirable to observe fast on 13, 14 and 15, have a bath each day, and give alms in the way of Allah.

2- In the night of "Ayyam Bayz" pray a 12 Rakaat prayer as under:

(i) In the night of the 13th pray 2 Rakaat:

In each Rakaat recite Surah Hamd (The Opening), Surah Al Yaa Seen, and Surah Al Mulk (Dominion).

(ii) In the night of the 14th pray 4 Rakaat: in 2 sets of 2 Rakaat, each exactly as (i),

(iii) In the night of the 15th pray 6 Rakaat: in 3 sets of 2 of 2 Rakaat, each exactly as (i),

3- In the night of 15th:

(i) Recite Ziyaraat of Imam Hussein (a.s)

(ii) Pray the following 12 Rakaat prayer in 6 sets of 2 Rakaat each:

In every Rakaat recite:

Soorah Al Faatih’ah 4 times

Soorah Al Ikhlaas 4 times

Soorah Al Falaq 4 times

Soorah Al Kaafiroon 4 times

Soorah Al Naas 4 times

Soorah Al Qadr 4 times

Ayatul Kursi 4 times

Tasbihaat ul Arbaa’ 4 times

After every Salaam recite 4 times:

Allah! Allah! My Lord! I associate not anything with Him. I choose no protecting friend beside Him. That which Allah wills (come to pass). There is no might and no strength save in Allah, the Hightest, the Almighty.

4- On the 15th day:

(i) Pray prayers of Salman Farsi. A 10 Rakaat prayer, Pray in 5 sets of 2 Rakaat each. In every Rakaat recite Surah Hamd (The Opening) once, Surah Ikhlaas (The Purity)3 times and Surah Kafiroon ( the disbelievers) 3times.

Then after salaam raise both your hands towards the sky and recite:

There is no god save Allah, no one other than him; sovereignty belongs to HIM. All praise is for HIM alone, gives life, puts to death,(because) HE is ever living, Immortal; in His hand is the good, He is able to do all thing.

Then say:

O my Allah there is no obstacle when thou gives, and there is no access to anything when thou puts a stop; there is no profit in exerting ones self in a matter when thou "looks the other way" and recite the following:

The one true God! Single! Unique! The eternally besought! He did not choose any associate nor a son.

(ii) Recite Ziyaraat of Imam Hussein (a.s) and this Special Ziyaraat

(iii) Pray 4 Rakaat prayer in 2 sets of 2 Rakaat each.

After Salaam recite the following dua’a:

O my Allah! O He who puts the proud tyrants to shame! O He who glorifies the faithful! Thou was my choice at once when I came across many schools of thought (religions), Thou brought me into existence, a favor to me, though Thou was able to dispense with my creation, not needing me at all.

If not for Thy mercy I am of those who perish. Thou makes available reliable support to have an upper hand over my adversaries. If not for Thy help I am of those who shatter and break into pieces.

O He who sends forth mercy from its permanent self-generating origin, and brings out blessing from its depository.

O He who has reserved for Himself that which is the highest, and the loftiest, so His intimate friends, on account of His might, vie in honor and glory. O He before whom bend low the rulers, their necks burdened with the yoke of disgrace and abasement, panic-stricken, scared stiff, in awe of His absolute power.

I beseech Thee in the name of Thy Supreme Being that derives its meaning from Thy timeless eternal greatness, I beseech Thee in the name Thy timeless eternal Greatness that derives its meaning from Thy omnipotent authority; I beseech Thee in the name of Thy omnipotent authority with which Thou occupied the Arsh, and created all that which has been created by Thee; so they, unto Thee, are very obedient, to send blessing on Muhammad and on the people of his house.

^{* Source: duas.org}