The best form of speech

"Beware that their emit from your tongue a saying which will count against you on the Day of Judgement. Make sure that your tongue is continuously articulating the truth or that it remains silent as the Messenger of Allah said, "whosoever believes in Allah and the Last Day then let him speak only good or remain silent" (Bukhari)."
Muhammad ibn Saalih al-'Uthaymeen 

"The best form of speech is that in which a little removes the need to say more, and the meaning is self evident in the words."
Ibn Abbas

"Your tongue is like a horse. If you take care of it, it takes care of you; if you treat it badly, it treats you badly." -Arabic proverb

"I found true seclusion to be in the solitude of the tongue." 
-Wuhayb ibn Al Ward

'The one speaks (much) waits for Fitnah to occur whilst the one who is silent waits for Mercy to descend" -
Yazid ibn Abi Habib
Source: Jami' Bayan al-Ilm wa Fadhlihi

If it's evident that the person who stands besides you in Salah

Ibn 'Uthaymeen: 

"If it's evident that the person who stands besides you in Salah keeps moving their feet away from you (i.e. refuses to join feet) it is not from the Sunnah for you to move your foot closer (because then you'll end up standing with widespread feet)."

(Liqaa ash-Shahri 16)

You are an ape in the form of a human

Ibn 'Uthaymeen wrote:

"As for the person who believes in it (evolution theory) , we say to him:

"You are an ape in the form of a human."

(al-Qawl al-Mufîd (2/245))