Verses with the word fornication in the Old Testament (4 verses):

2 Chronicles 21:11
Moreover he made high places in the mountains of Judah and caused the inhabitants of Jerusalem to commit fornication, and compelled Judah thereto.

Isaiah 23:17
And it shall come to pass after the end of seventy years, that the LORD will visit Tyre, and she shall turn to her hire, and shall commit fornication with all the kingdoms of the world upon the face of the earth.

Ezekiel 16:26
Thou hast also committed fornication with the Egyptians thy neighbours, great of flesh; and hast increased thy whoredoms, to provoke me to anger.

Ezekiel 16:29
Thou hast moreover multiplied thy fornication in the land of Canaan unto Chaldea; and yet thou wast not satisfied therewith.