There is no Hebrew word for 'Rainbow'. The word translated as rainbow in Genesis 9:13 is the same word translated elsewhere as an 'archer's bow'. What does that mean? It means that God didn't simply throw a rainbow up in the sky as a symbol of his peace and love for mankind. It means that he placed his bow upon the clouds as a sign of his pledge that he was retiring flooding rains from his arsenal of judgment against rebel humans.
Rain-bows, then, are ultimately weapons of judgement, not symbols of love and peace. They only become symbols of love and peace when we recognize which direction the working end of those weapons are pointing. They are pointed toward heaven, towards God.
The judgement of God against human rebellion and insurrection fell upon God himself, in the person of Jesus Christ upon the cross. He bore the torrent of the Father's wrath against sin by dying the death his people deserved, so that all who are found in Jesus, the true Ark of our Salvation, will escape the flooding fire of God's judgement.
Turn back to God, find sanctuary in Jesus, and you will be saved from the wrath that is to come.
