The Prophet ﷺ, Abu Bakr, and Umar, may Allah be pleased with them both, would start their recitation with: "All the praise and thanks be to Allah, the Lord of all that exists. (Using translation from Nasāʾī 902)  

كَانَ النَّبِيُّ ﷺ وَأَبُو بَكْرٍ وَعُمَرُ يَسْتَفْتِحُونَ الْقِرَاءَةَ بِالْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ  

"I prayed with the Prophet ﷺ and with Abu Bakr and Umar, may Allah be pleased with them both, and they started with "All the praise and thanks be to Allah, the Lord of all that exists." (Using translation from Nasāʾī 903)   

«صَلَّيْتُ مَعَ النَّبِيِّ ﷺ وَمَعَ أَبِي بَكْرٍ وَمَعَ عُمَرَ فَافْتَتَحُوا بِالْحَمْدِ»