‘Abdu’l-Bahá immediately chastened His attendant by slapping him hard in the face

Soon after the arrival of Bahá’u’lláh and His party in ‘Akka the Governor visited the barracks for inspection. ‘Abdu’l-Bahá, accompanied by a few believers, went to see him. But the Governor was discourteous and spoke to them in a provocative manner. He threatened to cut the supply of bread if one of the prisoners went missing and then ordered them back to their room. One of the Master’s attendants could not bear to remain silent after such insulting treatment. He retorted with rage and hurled back at the Governor some offensive remarks. ‘Abdu’l-Bahá immediately chastened His attendant by slapping him hard in the face in front of the Governor and ordering him to return to his room.

The Revelation of Bahá'u'lláh, Volume 3, Chapter 1

http://www.peyman.info/cl/Baha'i/Others/ROB/V3/p001-031Ch01.html