We see here where God tells the Prophet to speak words of comfort to His people telling them that their warfare is over. It's the peace that would be during the rest of Hezekiah's day, because his children would face lost of goods and captivity. To us, we are commissioned to tell the good news -Gospel -that our carnal warfare is over and that we can rest in the comfort that Jesus has overcome for us and that we can rest in Him -His Word-, that is the promises of God.