When seeing the new moon
Sighting the crescent
Arabic
اللَّهُمَّ أَهِلَّهُ عَلَيْنَا بِالأَمْنِ وَالإِيمَانِ، وَالسَّلاَمَةِ وَالإِسْلاَمِ
Transliteration
Allāhumma ahillahu ʿalaynā bi-al-amni wa al-īmān, wa as-salāmati wa al-Islām.
English
"O Allah, let it rise over us with security, with faith, with peace, and with Islam."
Source: Sunan at-Tirmidhī 3451