When the Prophet of Allah (ﷺ) saw the new moon, he said: "a new moon of good and right guidance; a new moon of good and right guidance; a new moon of good and right guidance. I believe in Him Who created you" three times. He would then say: "Praise be to Allah Who has made such and such a month to pass and has brought such and such a month."
Reference: Sunan Abi Dawud 5092 In-book : Book 43, Hadith 320 English translation : Book 42, Hadith 5073
Help us gift a modern, ad-free Islamic application for the Muslim Ummah. Your donation will be recorded as Sadaqah Jariyah in your book of deeds, In Sha Allah.