'Testify' in the Bible

Heaven and earth will testify against what has occurred today: you'll surely and swiftly be destroyed from the land that you are about to possess by crossing the Jordan River. You won't live long in it, because you'll certainly be exterminated.

If you neglect the LORD your God, follow other gods, and serve and worship them, I testify to you today that you will certainly be destroyed.

I call heaven and earth to testify against you today! I've set life and death before you today: both blessings and curses. Choose life, that it may be well with you you and your children.