They are secrets of God and few know them. Prophet said some of them. And the infallible Imams said some of them in their Hadiths.
For example about کهیعص most of Shia scholars believe it is related to Karbala happening.
And it is:
ک is for کربلا Karbala
ه is for هلاک Killing of family of prophet (Ahl Bayt)
ی is for يزيد Yazid who was cruel on Hussain S.A
ع is for عطش his thirsty
ص is for صبر his patience
This is said by Imam Mahdi the 12th Imam of Shia. And this Hadith of Imam Mahdi S.A can be seen in many Shia Hadith books like:
- کمالالدین وتمام النعمة، شیخ صدوق
- احتجاج، طبرسی
- تفسیر البرهان، سیدهاشم بحرانى
- بحار الانوار، علامه مجلسی
The Hadith says:
I was with Imam Askari S.A (the 11th Imam and father of Imam Mahdi S.A) and someone asked about کهیعص . Imam said ask my child Mahdi. Then Imam Mahdi S.A said: these letters are from unseen secrets. And God said them to his slave Zakariya (Zechariah) and then God told its story to prophet Muhammad PBUH and it is Zechariah asked God to teach him the holey five names. So Gabriel came to him and taught them to him. When Zechariah recited names of Muhammad and Ali and Hasan his sadness disappeared but when recited Hussain name sob came to him and so he wondered. So asked God the reason of this. Then God said to him the story of Karbala and then said کهیعص and said ک is for کربلا Karbala ه is for هلاک Killing of amily of prophet (Ahl Bayt) ی is for يزيد Yazid who was cruel on Hussain S.A ع is for عطش is thirsty ص is for صبر his patience
Ref:
Shia Hadith Books:
- کمالالدین وتمام النعمة، شیخ صدوق
- احتجاج، طبرسی
- تفسیر البرهان، سیدهاشم بحرانى
- بحار الانوار، علامه مجلسی
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