This is without a doubt the most well-known and widely-read little anthology of Prophetic hadith, known in Arabic as the Arba'in, or "The Forty." Imam al-collection Nawawi's is frequently the first and, in some cases, the only Hadith text that many Muslims throughout the world, from the east to the west, read in their lifetimes.

Each hadith in this book functions as a fundamental text for justification in at least one branch of Islamic science. The Hadith of the Arba'in are among the best examples of Allah's Prophet's ability to transmit a great deal in a small amount of words, yet as a result of their importance, they are also incredibly dense in meaning.