Sufyaan [ibn ‘Uyayanah] narrated to us from ‘Abdullaah ibn Deenaar from ‘Abdullaah ibn ‘Umar, May Allah be pleased him, that the Prophet, May peace and blessings be upon him, said,
“If you are a group of three, two of you should not engage in a private conversation, leaving out the third.” On another occasion, Ibn (Umar said that the Prophet ~ forbade two men in a group of three from conducting a private conversation, leaving out the third.”
(MusnadAh.mad, Vol. 2, p. 9. The isnaad of this hadeeth is Saheeh according to the conditions set by al-Bukhaaree and Muslim.)
Commentary
In al-Muwwaua’, Imaam Maalik reports a similar h.adeeth on the authority of ‘Abdullaah ibn Deenaar who said that he was with ‘Abdullaah ibn ‘Umar at the house of Khaalid ibn ‘Uqbah when a man came and wanted to speak to ‘Abdullaah ibn ‘Umar. ‘Abdullaah ibn Deenaar was the only other person present, so ‘Abdullaah ibn ‘Umar called another man so that they were four and said to ‘Abdullaah ibn Deenaar and the other man whom he had called, “Go a little way off together, because I heard the Messenger of Allah, peace, and blessings be on him, say, ‘Two individuals must not hold a private conversation to the exclusion of another.”‘ The Qur’an also says in this respect, “Secret counsels are only inspired by Satan in order that he may cause grief to the believers.” (Surat al-Mujaadilah, 58:10)
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)