Losing a pet is an experience that leaves a gaping hole in our hearts. I find that just talking about a rainbow bridge doesn't really help. It is a beautiful thought, but I am a Bible-believing Christian, so that led me to look up all references to rainbow in the Bible.
Although there is no mention of a 'rainbow bridge,' what I found was that the rainbow covenant God made with Noah wasn't just to mankind but to every living creature that was with him! It was a covenant between God and all of his creation! God made an eternal, binding promise to animals!
If they are temporary or if he didn't love them, why would he make this everlasting covenant with them? That inspired my journey to start at Genesis and walk through the entire Bible to see what God says. I decided to share the answer and hope that it blesses all who read it.
