Musnad Ahmad 456:33

I read to Abd al-Rahman: Malik [said]. My father said: And Ishaq narrated to us, he said: Malik narrated to us, from Salih ibn Kaysan, from Ubayd Allah ibn Abd Allah, from Zayd ibn Khalid al-Juhani, who said: The Messenger of Allah (peace and blessings of Allah be upon him) led us in the morning prayer at al-Hudaybiyah following rainfall that had occurred during the night. When he finished, he turned to the people and said: "Do you know what your Lord has said?" They said: "Allah and His Messenger know best." He said: "This morning, some of My servants became believers in Me—Ishaq said: and disbelievers in the stars, and some became believers in the stars and disbelievers in Me. As for the one who said: 'We have been given rain by the bounty of Allah and His mercy,' that one is a believer in Me and a disbeliever in the stars. And as for the one who said: 'We have been given rain by the rising of such-and-such star,' that one is a disbeliever in Me and a believer in the stars."