Ubay ibn Ka'b RA

Ubay ibn Ka'b RA was a Companion whom the Prophet ﷺ trusted with confidential news. In 3 AH, as soon as the Quraysh army left Makkah for Uhud, al-Abbas sent a trusted servant riding to Madinah with a letter detailing the army's size, horses and weapons. The servant found the Prophet ﷺ at Quba and handed him the letter. The Prophet ﷺ told Ubay to read it, and Ubay told him everything it contained. The Prophet ﷺ then instructed him, "Do not tell anybody about this news."