Exodus 5:4 (KJV)

And afterward Moses and Aaron went in, and told Pharaoh, Thus saith the LORD God of Israel, Let my people go, that they may hold a feast unto me in the wilderness.

And Pharaoh said, Who is the LORD, that I should obey his voice to let Israel go? I know not the LORD, neither will I let Israel go.

And they said, The God of the Hebrews hath met with us: let us go, we pray thee, three days' journey into the desert, and sacrifice unto the LORD our God; lest he fall upon us with pestilence, or with the sword.

And Pharaoh said, Behold, the people of the land now are many, and ye make them rest from their burdens.

And Pharaoh commanded the same day the taskmasters of the people, and their officers, saying,

Ye shall no more give the people straw to make brick, as heretofore: let them go and gather straw for themselves.

And the tale of the bricks, which they did make heretofore, ye shall lay upon them; ye shall not diminish ought thereof: for they be idle; therefore they cry, saying, Let us go and sacrifice to our God.

Let there more work be laid upon the men, that they may labour therein; and let them not regard vain words.