Ibn Mas'ud RA said,

"Do not learn knowledge for three reasons: to argue with foolish people, or to dispute with fugaha, or to turn people's faces towards you. Seek from your words and your actions that which is with Allah because it endures and what is other than it will go away."

[The Compendium of Knowledge and
Wisdom by In Rajab Al-Hanbali رحمه الله pg. 15]

@FadingShadow

Ibn al-Jawzī رحمه الله:

“Liberate your tongue to indulge in the remembrance of Allāh, but if you are unable to do so, then at the very least, restrain it from backbiting.”

[Kitāb al-Laṭā’if fil-Wā‘iẓ | P. 173]

Az-Zalzalah 99:8
وَمَن يَعۡمَلۡ مِثۡقَالَ ذَرَّةٍ شَرًّا يَرَهُۥ


And whosoever does evil equal to the weight of an atom (or a small ant), shall see it.

Divehi - Abu Bakr Ibrahim Ali (Bakurube)
(8) އަދި ނުބައިކަމުގެ ތެރެއިން ޛައްރެއްގެ މިންވަރުގެ ކުޑަ ޢަމަލެއްކޮށްފަވާ މީހަކުވެސް އެކަން ދެކޭނެއެވެ. (އެއަށް އޭނާ މަސްއޫލު ވާންޖެހޭނެއެވެ.)

"The heart that loves Allah,
loves being exhausted and exerting itself for Allah; surely, Allah's love is not acquired through comfort"

[Imam Ibn Rajab, Majmoo' ar-Rasaa'il]

@FadingShadow