“As soon as I leave you,” Moses said, “I will pray to the LORD, so that tomorrow the swarms of flies will depart from Pharaoh and his officials and his people. But Pharaoh must not act deceitfully again by refusing to let the people go and sacrifice to the LORD.”
Jewish Publication Society of America Version (JPS1917) - Exodus 8:29 >(8-25) And Moses said: 'Behold, I go out from thee, and I will entreat the LORD that the swarms of flies may depart from Pharaoh, from his servants, and from his people, tomorrow; only let not Pharaoh deal deceitfully any more in not letting the people go to sacrifice to the LORD.'