I heard of a hadith concerning a bedouin coming to the prophet (sallahu alayhi wa sallam) and insulting him, then telling him he would only believe if his lizard made testimony to the Prophet, at which point the lizard proclaimed the truth of Allah and his Messenger. Is this authentic?
This Hadith was reported by Bayhaqi and mentioned by Hafidh Ibn Kathir in Bidayah wa Nihaya (6/165)]. It is a baatil Hadith as Shaikh al-Albani rahimahullah mentioned in Irwaa al-Ghalil (5/108). He cited Imam Dhahabi rahimahullah saying:
قلت : صدق والله البيهقي فإنه خبر باطل
I say, Bayhaqi spoke the truth, by Allah. Verily it is a baatil [false] report.
Hafidh Ibn Hajr declared it very weak in Talkhees al-Kabeer and in Lisaan al-Mizaan as did other Scholars of Hadith.
And Allah Knows Best
Faisal Ibn Abdul Qaadir Ibn Hassan