The 40th nuclear dike contains 42 hadiths about the Messenger of Allaah (peace and blessings of Allaah be upon him), as the imam said
The nuclear 40 is an author containing forty Hadiths, a noble prophet, compiled by: Imam al-Nawawi, who committed to collect them to be true, and the reason of nuclear reason for the collection of forty said:

Of the scholars of the group of forty in the fundamentals of religion, and some in the branches and some in the jihad, and some in asceticism and some in the speeches, all valid purposes, may Allah be pleased with her intentions. I have seen the collection of forty of the most important of all, which is a modern forty containing all of this, and each talk of a great rule of religion, which scientists have described as the orbit of Islam, or describe Islam or a third or so.