Aishah reported that whenever something alarmed the Prophet ﷺ, he would say, "Allah, Allah is my Lord. I associate nothing with Him."
أن النبي ﷺ كان إذا راعه شيء قال: الله الله ربي، لا أشرك به شيئا.
No references are available.
Narrated by Nasai in Amal al-Yawm wal-Layla (657), Tabarani in Musnad Shamiyin (424), and Ibn Muqri in his Mujam (872), all through the route of Sahl bin Hashim, who said, Thawri narrated to us, from Thawr bin Yazid, from Khalid bin Madan, from Thawban, and he related it.Its chain is hasan because of Sahl bin Hashim Habashi. Abu Hatim and Nasai said, "There is no harm in him," and Ibn Hibban mentioned him among the trustworthy. Ibn Hajar also graded it hasan in Futuhat Rabbaniya (12/4).His saying, "when it alarmed him," comes from rawe, which means terror and fear.