9. While the New Testament does not contain any specific texts which assert that the infant children of believers are members of the church by virtue of their birth yet the New Testament abounds in passages which cannot be reasonably explained but in harmony with this doctrine.
The first passage I would like to adduce is not actually a New Testament passage, but a passage from Isaiah which speaks of New Testament times. Speaking of the glory of the latter days when the wolf and the lamb will feed together, Isaiah declares, “Behold, I create new heavens, and a new earth, and the former shall not be remembered, nor come into mind. For as the days of a tree are the days of my people, and my elect shall long enjoy the work of their hands. They shall not labor in vain, nor bring forth for trouble; for they are the seed of the blessed of the Lord, and their offspring with them (Isaiah 65:17, 22, 23).
What Christ said in Matthew 19:13-15 cannot be understood without presupposing the church membership of infants. When Jesus said, “Suffer the little children to come unto me, and forbid them not, for of such is the kingdom of heaven,” there are a couple of things which are very notable. First of all, when we compare this passage with its parallels, we find that these children were, indeed, infants (βρέφη). After all, Christ “took them in his arms.”
But what is more remarkable are his words, “of such is the kingdom of heaven.” In other words, the kingdom of heaven belongs to them. It is the same form of expression Christ uses in his Sermon on the Mount when he says, “Blessed are the poor in spirit, for theirs is the kingdom of heaven;” “Blessed are they that are persecuted for righteousness sake, for theirs is the kingdom of heaven.” This precludes the objection appealed to by some that the words “of such is the kingdom of heaven” means that the kingdom of heaven is made up of such as resemble little children in spirit. If we must take that to be the meaning in Matthew 19, why aren’t we forced to take that to be the meaning in the identical expressions found in the Sermon on the Mount? We might as well say that the kingdom of heaven doesn’t belong to those who are poor in spirit, but only to those who resemble the poor in spirit. Or that the kingdom of God does not belong to those who are persecuted righteousness sake, but only those who resemble those who are persecuted for righteousness sake. Christ’s language obviously means that the kingdom of heaven was really theirs of whom He spoke, that it truly belongs to them, that they are the heirs of it, just as the poor in spirit and those who are persecuted for righteousness sake.
But what do we make of the phrase “the kingdom of heaven” as it is used in this passage? Obviously, we have to understand as referring to visible church, i.e., the visible kingdom of Christ. Anywhere in the New Testament where this phrase is used, one will find that this is the general import of the expression. If this be the case, then we have Christ asserting in direct and pointed terms the divine warrant of infant church membership. But even on the supposition that the “kingdom of heaven” refers to the kingdom of glory our argument is not affected, but rather strengthened. If the kingdom of glory belongs to the infant children of believers, how much more would they have a right to those privileges in the church on earth?
Few people defend the automatic salvation of those who die in infancy with as much vigor as do Baptists. This is ironic, it seems. They trip over themselves to make sure infants have automatic rights to heaven, but with equal vigor deny them the automatic right to church-membership. Affirming this about the children of believers who die in infancy is inconsistent enough, but most Baptists affirm that all who die in infancy go to heaven, regardless of their parents’ spiritual state.
There is another passage of Scripture which strongly speaks the same language. I’m referring, of course, to Peter’s sermon on the day of Pentecost. When a multitude of the hearers on that day fell under the conviction of the Holy Spirit, and said to Peter and the rest of the apostles, “Men and brothers, what shall we do?” What was the answer of Christ’s inspired apostle? “Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins. And you will receive the gift of the Holy Spirit. The promise is for you and your children and for all who are far off—for all whom the Lord our God will call.” Obviously Peter was speaking of the promise of God to His covenant people, namely, the promise in which He engages to be their God and to constitute them as His covenant people. This is the covenant promise God made to Abraham which He sealed by the sacrament of circumcision. Peter cites the covenant promise which was sealed by circumcision in the same breath as his admonition for them to be baptized. If the tying together of these two ideas in one breath has no significance, then we search in vain for a connection in anything Scripture links together.
One final passage I will adduce is 1 Corinthians 7:14. – “For the unbelieving husband is made holy because of his wife, and the unbelieving wife is made holy because of her husband. Otherwise your children would be unclean, but as it is, they are holy.”
The big question here is: In what sense does the believing parent sanctify the unbelieving one so that their children are holy? It can't possibly mean that the believing spouse is always instrumental in the regeneration and sanctification of their partner and their children. No one who intelligently reads their Bible could understand this. Not to mention the fact that we all frequently observe the opposite. Some have understood this to mean that the children in these mixed marriages were illegitimate; meaning that the Corinthian Christians were under the impression that wedlock between believers and unbelievers was invalid. This is, of course, nonsense. No other passage of Scripture containing the words “holy” and “unclean” gives countenance to such a construction.
It’s actually the words “holy” and “unclean” pitted against each other that give us the insight into how to understand this passage. These two terms have a long history of ecclesiastical usage in the Old Testament. Levitical law labeled everything “clean” or “unclean.” By these two terms all of life was spiritualized. The pious Jew was brought face to face in his daily mundane activities with the spiritual reality that sin and the spiritual defilement that came with it was transferable and/or communicable; while cleanness or moral purity was not. Human society itself was divided into these two categories based on their relation to the covenant of God, which is why the Jews were constantly called a “holy people.” They were separated from the rest of the world which was left by God wallowing in the filth of sin.
In the Corinthian situation, it appears that there were many believers who were married to unbelievers. Some were obviously married before their conversion. Others were foolish enough to marry unbelievers after their conversion. We know this from Paul’s later admonition against being “unequally yoked.” Paul's intention here is, under the inspiration of the Holy Spirit, to assure the believer that, even though they had an unbelieving spouse, they did not have to fear that their children were thereby excluded from the covenant of God.
This passage clearly establishes the church-membership of infants in yet another way. It operates on the assumption of the principle that children of whom both parents are believers automatically belong to the Church of God. Without this assumption the question Paul is handling would never have come up. The difficulty arises when, assuming that the children are in God's covenant when both parents are believers, - when we have children of whom only one parent is a believer. This is the only circumstance in which this question would arise. A Corinthian would say, “I see the children of my Christian brothers owned as members of the Church. I also see the children of unbelievers rejected along with the unbelieving parents. I get that. But, here is my concern: I believe in Christ, yet my husband (or my wife) does not believe. What is to become of my children? Are they to be admitted with me or are they to be cast off with my partner?" It is hard to see why Paul would dissuade believers from separating from their unbelieving spouse on any other supposition.