Exodus 10:24

21 And Jehovah saith unto Moses, `Stretch out thy hand towards the heavens, and there is darkness over the land of Egypt, and the darkness is felt.`

22 And Moses stretcheth out his hand towards the heavens, and there is darkness -- thick darkness in all the land of Egypt three days;

23 they have not seen one another, and none hath risen from his place three days; and to all the sons of Israel there hath been light in their dwellings.`

24 And Pharaoh calleth unto Moses and saith, `Go ye, serve Jehovah, only your flock and your herd are stayed, your infants also go with you;`

25 and Moses saith, `Thou also dost give in our hand sacrifices and burnt-offerings, and we have prepared for Jehovah our God;

26 and also our cattle doth go with us, there is not left a hoof, for from it we do take to serve Jehovah our God; and we -- we know not how we do serve Jehovah till our going thither.`

27 And Jehovah strengtheneth the heart of Pharaoh, and he hath not been willing to send them away;