.. and the Qur’aan was sent down on the twenty-fourth of Ramadaan

It was narrated by Ahmad and by al-Tabaraani in al-Mu’jam al-Kabeer that Waathilah ibn al-Asqa’ (may Allaah be pleased with him) said:

The Messenger of Allaah (sal allahu 'alayhi wa sallam) said:

The Scriptures of Ibraaheem were sent down on the first of the month of Ramadaan.
The Tawraat was sent down on the sixth of Ramadaan.
The Injeel was sent down on the thirteenth of Ramadaan.
The Zaboor was sent down on the eighteenth of Ramadaan, and
The Qur’aan was sent down on the twenty-fourth of Ramadaan.

Classed as hasan by al-Albaani in al-Silsilah al-Saheehah, 1575.