A true word needs no oath.
More Turkish Proverbs:
The wise man says what he knows; the fool doesn't know what he is saying.Turkish
Tell a lie on Saturday and you will be ashamed on Sunday.
Turkish
Things that are weak will break -- as men do who think they are strong.
Turkish
A thousand years hence the river will run as it did.
Turkish
A thread-bare coat is armour proof against highwaymen.
Turkish
A thousand regrets do not cancel one debt.
Turkish