Sunan ad-Darimi 1729
Saʿīd b. Sulaymān > ʿAbd al-Raḥman b. ʿUthmān b. Ibrāhīm from my father > Abīh And from his uncle > Ibn ʿUmar
The translation of the given text in Arabic to English is: "When the Prophet ﷺ saw the new moon, he used to say, 'Allah is the greatest! O Allah, let this crescent be a crescent of security, faith, safety, Islam, and success in what our Lord loves and is pleased with. And your Lord is Allah.'" – Weak Chain
أَخْبَرَنَا سَعِيدُ بْنُ سُلَيْمَانَ عَنْ عَبْدِ الرَّحْمَنِ بْنِ عُثْمَانَ بْنِ إِبْرَاهِيمَ حَدَّثَنِي أَبِي عَنْ أَبِيهِ وَعَمِّهِ عَنْ ابْنِ عُمَرَ قَالَ
كَانَ رَسُولُ الله ﷺ إِذَا رَأَى الْهِلَالَ قَالَ «اللَّهُ أَكْبَرُ اللَّهُمَّ أَهِلَّهُ عَلَيْنَا بِالْأَمْنِ وَالْإِيمَانِ وَالسَّلَامَةِ وَالْإِسْلَامِ وَالتَّوْفِيقِ لِمَا يُحِبُّ رَبُّنَا وَيَرْضَى رَبُّنَا وَرَبُّكَ اللَّهُ» – إسناده ضعيف