What is the ruling on saying "Our Lord, and to You be all praise and gratitude" after bowing (ruku'), and "Prayer is better than sleep" in the call to prayer (adhan) for Fajr, and "Indeed, You do not break the promise" in the supplication (du'a) after the adhan, and "Allah Almighty has spoken the truth" after reciting the Qur'an? And what is the extent of the authenticity of the hadith: "If you see a man frequenting the mosques, then bear witness to his faith"?

Innovation in religion (bid'ah) is one of the most dangerous sins because it is a misguidance and a cause for entering Hellfire. The Prophet, peace and blessings be upon him, warned against it, saying: "Beware of newly invented matters, for every innovation is a misguidance." And he said: "Indeed, Allah has withheld repentance from every innovator," meaning that he will not be guided to repentance. Therefore, one should adhere to the established prophetic remembrances and deeds and not approve of what has not been authentically established, for the best deeds are those that are most constant and most sincere. Scholars have differed regarding the hadith (definition): "If you see a man frequenting the mosques..." between those who authenticated it and those who weakened it. As for "Indeed, You do not fail in Your promise," Al-Bayhaqi narrated it, and Ibn Qudamah explicitly stated its permissibility.