Riyad as-Salihin

Abu Hurairah (May Allah be pleased with him): The Prophet (ﷺ) said, "Iman has over seventy branches - or over sixty branches - the uppermost of which is the declaration: 'None has the right to be worshipped but Allah'; and the least of which is the removal of harmful object from the road, and modesty is a branch of Iman."

[Al-Bukhari and Muslim].