“A word can also be one of the means used by Satan to stir enmity; it is sometimes perceived in a different meaning in people’s conversation; so it creates an environment of hatred. It is for this reason that Allah swt has ordered us to utter only good expressions: “Say to My slaves that they should only say the best. Satan wants to stir up trouble between you. Satan is an outright enemy to man.” Surah al Israa, verse 53.
Sayyid Qutb said, interpreting the verse, that people should say what is best all the time and regarding every matter; they should select the good expressions, in order to prevent Satan from disturbing their love and friendship. Satan creates enmity between brothers with just one vulgar word slipped, which would be followed by a bad reply; so a spirit of love and affection would change into one of controversy and enmity. A good word heals any injury of the heart and encourages everyone to respect one another.”
Source:
How to Protect Yourself From Jinn and Shaytan by Waheed Abdulsalaam Baly
Al Muqarraboon 