Without conversion of heart we cannot serve God on earth. We have naturally neither faith, nor fear, nor love, toward God and His Son Jesus Christ. We have no delight in His Word. We take no pleasure in prayer or communion with Him. We have no enjoyment in His ordinances, His house, His people, or His day. We may have a form of Christianity, and keep up a round of ceremonies and religious performances. But without conversion we have no more heart in our religion than a brick or a stone. Can a dead corpse serve God? We know it cannot. Well, without conversion we are dead toward God. Look round the congregation with which you worship every Sunday. Mark how little interest the great majority of them take in what is going on. Observe how listless, and apathetic, and indifferent, they evidently are about the whole affair. It is clear their hearts are not there! They are thinking of something else, and not of religion. They are thinking of business, or money, or pleasure, or worldly plans, or bonnets, or gowns, or new dresses, or amusements. Their bodies are there, but not their hearts. And what is the reason? What is it they all need? They need conversion. Without it they only come to church for fashion and form’s sake, and go away from church to serve the world or their sins. But this is not all. Without conversion of heart we could not enjoy heaven, if we got there. Heaven is a place where holiness reigns supreme, and sin and the world have no place at all. The company will all be holy; the employments will all be holy; it will be an eternal Sunday. Surely if we go to heaven, we must have a heart in tune and able to enjoy it, or else we shall not be happy. We must have a nature in harmony with the element we live in, and the place where we dwell. Can a fish be happy out of water? We know it cannot. Well, without conversion of heart we could not be happy in heaven.Look round the neighborhood in which you live and the persons with whom you are acquainted. Think what many of them would do if they were cut off for ever from money, and business, and newspapers, and cards, and balls, and races, and hunting, and shopping, and worldly amusements! Would they like it? Think what they would feel if they were shut up forever with Jesus Christ, and saints, and angels! Would they be happy? Would the eternal company of Moses, and David, and St. Paul be pleasant to those who never take the trouble to read what those holy men wrote? Would heaven’s everlasting praise suit the taste of those who can hardly spare a few minutes in a week for private religion, even for prayer? There is but one answer to be given to all these questions. We must be converted before we can enjoy heaven. Heaven would be no heaven to any child of Adam without conversion.Let no man deceive us. There are two things which are of absolute necessity to the salvation of every man and woman on earth. One of them is the mediatorial work of Christ for us, His atonement, satisfaction, and intercession. The other is the converting work of the Spirit in us, His guiding, renewing, and sanctifying grace. We must have both a title and a heart for heaven. Sacraments are only generally necessary to salvation: a man may be saved without them, like the penitent thief. An interest in Christ and conversion are absolutely necessary: without them no one can possibly be saved. All, all alike, high or low, rich or poor, old or young, gentle or simple, churchmen or dissenters, baptized or unbaptized, all must be converted or perish.
— J.C. Ryle