You know that God is the only Lord. You know that He is to be worshiped in accordance with His holy Word. You know that the gospel is the only life to be had in this wretched world.
But remember also that this gospel proclaims a new creation, a new heaven and new earth. This wretched world has been overcome, and is in the process of being remade through the power of God. Who is he that overcomes? The one who has faith in God and in His conquering Son.
What are the signs that we know this? What are the indications of our faith? Objectively, the Bible teaches that we have the Word and we have the sacraments. What are the indications that we believe the word that we have heard? What are the indications that we have digested in faith the sacraments we have been given?
The biblical answer is that we must evidence love, laughter, peace, joy, gladness and simplicity of heart, goodness toward others, liberality, kindness, tender mercies, robustness in psalm-singing, the liberty of forgiveness – as well as a stern severity toward all who would turn our celebration of life into a funeral wake. We are the people of life, the people of His resurrection. Rejoice, therefore. With Paul, I say it again. Rejoice!