For what is our hope, or joy, or crown of rejoicing? Isn't it even you, before our Lord Jesus{TR adds "Christ"} at his coming?
In the presence of our Lord Jesus Christ at his coming - “When the Lord Jesus appears at the end of the world, then our highest source of happiness and honor will be your conversion and salvation.” Then their salvation would be a proof of his fidelity. It would fill his soul with the highest happiness, that he had been the means of saving them from ruin.