Why did belief in the Books come after belief in the Angels and before belief in the Messengers in the Hadith of Jibril?

The first thing incumbent upon a servant is faith in Allah, then in the angels, because revelation reaches the prophets through the angels: ﴿He sends down the angels with the inspiration of His command upon whom He wills of His servants﴾. Then come the Books, which are the revelation conveyed by the angel, and then the Messengers, who receive the revelation from the angels. Al-Razi and Al-Tayyibi mentioned that this order follows reality, as Allah sent the angel with the Book to the Messenger. This is among the subtle points of knowledge and not among its pillars.