حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبَانُ، حَدَّثَنَا قَتَادَةُ، أَنَّهُ بَلَغَهُ أَنَّ النَّبِيَّ صلى الله عليه وسلم كَانَ إِذَا رَأَى الْهِلاَلَ قَالَ ‏"‏ هِلاَلُ خَيْرٍ وَرُشْدٍ هِلاَلُ خَيْرٍ وَرُشْدٍ هِلاَلُ خَيْرٍ وَرُشْدٍ آمَنْتُ بِالَّذِي خَلَقَكَ ‏"‏ ‏.‏ ثَلاَثَ مَرَّاتٍ ‏.‏ ثُمَّ يَقُولُ ‏"‏ الْحَمْدُ لِلَّهِ الَّذِي ذَهَبَ بِشَهْرِ كَذَا وَجَاءَ بِشَهْرِ كَذَا ‏"‏ ‏.‏

Narrated Qatadah: When the Prophet of Allah (PBUH) 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." Translation Not Available

Book Ref: Sunan Abi Dawud Book 43 Hadith 5092
Web Ref:  Sunan Abi Dawud Book 42 Hadith 5073