Isaiah 66:10

Rejoice ye with Jerusalem - The idea which is presented in this verse is, that it is the duty of all who love Zion to sympathize in her joys. It is one evidence of piety to rejoice in her joy; and they who have no true joy when God pours down his Spirit, and, in a revival of religion, produces changes as sudden and transforming as if the earth were suddenly to pass from the desolation of winter to the verdure and bloom of summer; or when the gospel makes rapid advances in the pagan world, have no true evidence that they love God or his cause. Such scenes awaken deep interest in the bosoms of angels, and in the bosom of God the Saviour; and they who love that God and Saviour will rejoice in such scenes, and will mingle their joys and thanksgivings with the joys and thanksgivings of those who are thus converted and saved.

All ye that mourn for her - That sympathize in her sorrows, and that mourn over her desolations.