In Calvin’s somewhat lengthy treatment of the sacrament of baptism in His Institutes of the Christian Religion, he devotes nearly 2/3 of that space (around 35 pages or so in the McNeill edition, translated by Ford Lewis Battles) to the subject of infant baptism.
One of the many arguments that John Calvin makes in support of the practice of infant baptism is based upon the words of Jesus in Matthew 19:14, where our Lord says,
“Let the little children come to me and do not hinder them, for to such belongs the kingdom of heaven.” (ESV)
At first glance this statement does not appear to have much of anything to do with baptism at all. And yet, as Calvin goes on to say, “For we must not lightly pass over the fact that Christ commands that the infants be presented to him, adding the reason, ‘for of such is the Kingdom of Heaven'” (4.16.7). When one takes the time to consider Christ’s words in this passage regarding infants, it becomes clear that they really do have something to say about the basis for infant baptism.
Calvin goes on to explain:
“And thereupon he attests his will by his act when, embracing them, he commends them with his prayer and blessing to his father. If it is right for infants to be brought to Christ, why not also to be received into baptism, the symbol of our communion and fellowship with Christ? If the kingdom of heaven belongs to them, why is the sign denied them which, so to speak, opens to them a door into the church, that, adopted into it, they may be enrolled among the heirs of the kingdom of heaven?” (Ibid.)
Christ not only received these little ones, taking them up in His arms and blessing them (Mark 10:16), but, as if that were not enough, goes as far as to say that to such as these belongs the kingdom of heaven! And, as Calvin points out, if the kingdom belongs to them, how then can the “sign” or mark of that kingdom rightly be denied them?
Not only is the practice of infant baptism (also known as paedobaptism) the majority practice in the Christian church throughout the world, but it has been such ever since the apostolic age, and so throughout the history of the church. Simply put, it clearly has both the majority of the church as well as the majesty of history on its side. These considerations, while certainly not primary, must not lightly be set aside.
Add to that the undeniable fact that the sign of the covenant was explicitly commanded by the Lord to be applied to infants in the Old Testament (i.e. circumcision), and many of the arguments against infant baptism begin to crumble under their own weight. As Calvin puts it, “For what will they [i.e. critics of infant baptism] bring forward to impugn infant baptism that may not be turned back against circumcision?” (Institutes, 4.16.9).