Musnad Abu Ya'la al-Mawsili 117:184

Ishaq ibn Abi Isra'il narrated to us, Abd al-Samad narrated to us, Shu'bah narrated to us, from Thabit, who said: I heard Anas saying to a woman of his family, "Do you know such-and-such a woman? Indeed, the Messenger of Allah (may Allah bless him and grant him peace) passed by her while she was weeping over a grave. He said to her, 'Fear Allah and be patient.' She said, 'Leave me alone, for you are not afflicted by my calamity,' and she did not know him. It was said to her, 'It is the Messenger of Allah.' So, something like death seized her. She came to his door and did not find a doorkeeper at it. She said, 'O Messenger of Allah, I did not know you.' He said to her, 'Indeed, patience is at the first shock.'"