when the Messenger of Allah stood on top of As-Safa, he recited the Takbir three times and said: "La ilaha illallah, Wahdahu la sharika lah, lahul-mulku wa lahul-hamdu, yuhyi wa yumitu, wa huwaala kulli shayin qadir (There is none worthy of worship except Allah alone with no partner or associate, His is the dominion and to Him be praise, He gives life and death, and He has power over all things)." He did three times, and supplicated, and did the same a top Al-Marwah. (Using translation from Nasāʾī 2972)  

أَنَّ رَسُولَ اللهِ ﷺ كَانَ إِذَا وَقَفَ عَلَى الصَّفَا يُكَبِّرُ ثَلَاثًا وَيَقُولُ لَا إِلَهَ إِلَّا اللهُ وَحْدَهُ لَا شَرِيكَ لَهُ لَهُ الْمُلْكُ وَلَهُ الْحَمْدُ وَهُوَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ يَصْنَعُ ذَلِكَ ثَلَاثَ مَرَّاتٍ وَيَدْعُو وَيَصْنَعُ عَلَى الْمَرْوَةِ مِثْلَ ذَلِكَ