Yonah 3:3-5

Orthodox Jewish Bible

³ So Yonah arose, and went unto Nineveh, according to the Devar Hashem. Now Nineveh was an exceeding ir gedolah of a journey of shloshet yamim.

⁴ And Yonah began to enter into the city one day’s journey, and he cried out and preached, and said, Yet arba’im yamim (40 days), and Nineveh shall be overthrown.

⁵ So the people of Nineveh had emunah in Elohim, and proclaimed a tzom, and put on sackcloth, from their gedolim even to their ketanim.