Praise be to Allah,
[Muhammad] ibn Abu ‘Adiyy narrated to us from Humayd [at-Taweel] from Anas ibn Maalik who said,
“Allah’s Messenger (PBUH) said, ‘The [true, good] dream of a believer is one of forty-six parts of prophethood.”‘
(Musnad Ahmad, p. 106. The isnaad of this hadeeth is Saheeh according to the conditions set by al-Bukhaaree and Muslim.)
Source:
Thulaathiyyaat Musnad Ahmad ibn Hanbal (may Allah have mercy on him)
Reports of Imaam Ahmad that have only three narrators between him and the Prophet, peace, and blessings be upon him.
Shaykh Muhammad ibn Ahmad ibn Saalim as–Saffaareenee al–Hanbalee ~(1114 –1188 AH)