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

Genesis 42:15
Hereby ye shall be proved: By the life of Pharaoh ye shall not go forth hence, except your youngest brother come hither.

Genesis 42:33
And the man, the lord of the country, said unto us, Hereby shall I know that ye are true men; leave one of your brethren here with me, and take food for the famine of your households, and be gone:

Numbers 16:28
And Moses said, Hereby ye shall know that the LORD hath sent me to do all these works; for I have not done them of mine own mind.

Joshua 3:10
And Joshua said, Hereby ye shall know that the living God is among you, and that he will without fail drive out from before you the Canaanites, and the Hittites, and the Hivites, and the Perizzites, and the Girgashites, and the Amorites, and the Jebusites.