Ibnul Hâj reported that Al-Imâm Al Bukhari رحمه الله Once left his country to some of the Mashaayikh (of Hadith) so that he may narrate some Ahâdeeth from them. Once Imam Al-Bukhari sat with him (I.e. a shaykh) a small child came to him and the shaykh clinched his own hand so that the child may think that there was something in it and the child may come to him and give him that which was in his hand.

Imam Al-Bukhari then stood up and left him off and he didn’t narrate any Ahâdeeth from him due to him seeing that (his action) was a Disparagement upon his Narration”

[Al-Madkhal By Ibnul-Hâj P119]