Dhikr of Rukū‘
Issue No.931- It is obligatory to utter a dhikr in rukū‘. One should, as an obligatory precaution, say "سُبْحانَ اللهِ" three times or "سُبْحانَ رِبِّىَ الْعَظِيمِ وَ بِحَمْدِهِ" once, and it should be uttered in correct Arabic. It is recommended that the dhikr be repeated three or five or seven times.