The Prophet (Sallallaahu `alayhi wa sallam) said:
“The most truthful of speech is the Book of Allah and the best of guidance is the guidance of Muhammad, and the most evil of things are those which are newly-invented.”

A desert Arab came to the Prophet of Allah (Sallallaahu `alayhi wa sallam) and said,
“Teach me a word that i can say.”
The Messenger (Sallallaahu `alayhi wa sallam) told him to say:
‘There is none worthy of worship but Allah, Who has no partner, Allah is the Great, the Most Great, and praise is to Allah in abundance, glory is to Allah, Lord of the worlds. There is no power and no might but by Allah the Mighty, the Wise.’
The desert Arab said,
“That is for my Lord, but what …

Al-Bukhari reported on the authority of Abu Hurairah (Radiyallaahu `anhu) that Allah’s Messenger (sallallaahu ‘alayhi wa sallam) said:
“The Hour will not come until my nation will follow completely and literally the errors of the previous nations.”

The Prophet of Allah (Sallallaahu `alayhi wa sallam) said:
“Whoever imitates a people is one of them.”

The Prophet of Allah (Sallallaahu `alayhi wa sallam) said,
“The best of fasts besides the month of Ramadhan is the fasting of Allah’s month of Muharram.”

Abu Dharr and Muadh bin Jabal (Radiyallahu `anhuma) reported that the Prophet (Sallallaahu `alayhi wa sallam) said,
“Fear Allah wherever you are, do good deeds after doing bad ones, the former will wipe out the latter, and behave decently towards people”

Abu Hurairah (Radiyallaahu `anhu) reported, I heard the Messenger of Allah (Sallallaahu `alayhi wa sallam) saying,
“By Allah, I seek Allah’s forgiveness and repent to Him more than seventy times a day.”

The Prophet Muhammad (Sallallaahu `alayhi wa sallam) said,
“Every son of Adam makes mistakes, and the best of those who make mistakes are those who repent”