From Sahih Muslim (Hadith 5705):
Anas reported that a Jewess came to Allah's Messenger (ﷺ) with poisoned mutton and he took of that what had been brought to him (Allah's Messenger). (When the effect of this poison were felt by him) he called for her and asked her about that, whereupon she said:I had determined to kill you. Thereupon he said: Allah will never give you the power to do it. He (the narrator) said that they (the Companion's of the Holy Prophet) said: Should we not kill her? Thereupon he said: No. He (Anas) said: I felt (the affects of this poison) on the uvula of Allah's Messenger
Reference: Muslim 5705