Exodus 8:29-31

New Revised Standard Version, Anglicised Catholic Edition

²⁹ Then Moses said, ‘As soon as I leave you, I will pray to the Lord that the swarms of flies may depart tomorrow from Pharaoh, from his officials, and from his people; only do not let Pharaoh again deal falsely by not letting the people go to sacrifice to the Lord.’

³⁰ So Moses went out from Pharaoh and prayed to the Lord. ³¹ And the Lord did as Moses asked: he removed the swarms of flies from Pharaoh, from his officials, and from his people; not one remained.