Before an answer can be provided, however, we must admit that baptism can be a divisive subject for Christians, especially when it comes to the proper recipients of the sacrament.  Let me offer a few reasons why this might be the case:
 
1.  Misunderstandings
Misunderstandings promote division and there are many misunderstandings about infant baptism. It is important for us to point out that just because a church practices infant baptism does not mean that it refuses to baptize adults as well.  In my initial pastoral experience as a minister in Scotland I discovered that this was a very common misunderstanding among Credobaptists (those who exclusively practice believer’s baptism.)  The assumption seemed to be that Paedobaptists (those who practice infant baptism) deny the sacrament to adults.  This assumption is false.  All Paedobaptists (to my knowledge at least) believe that adult converts from non-Christian backgrounds are to be baptized according to the clear example set forth in the New Testament.  
 
2.  Cultural Norms
We have to acknowledge a particular cultural difficulty in addressing the issue of Paedobaptism.  We are Americans and the fact is that most American evangelicals do not practice infant baptism.  Instead they prefer to baptize only those who have verbally professed faith in Christ.  But it is important for American evangelicals to understand that though their baptismal practice is the majority position in America evangelical churches it is the minority position throughout the rest of the world and throughout the history of the Church.
 
3.  Textual Difficulties
It is proper to acknowledge the textual challenges that exist for anyone attempting to define and defend their baptismal practice regardless of what that practice might be.  For we Paedobaptists this means we must honestly admit that there is no passage in the New Testament explicitly commanding us to baptize infants.  However, those who oppose Paedobaptism must also acknowledge that there is no passage explicitly forbidding the baptism of infants, let alone affirming the baptism of only those capable of verbally professing their faith.
 
With these preliminary considerations out of the way I think that we can now make a brief case for infant baptism by offering a threefold answer to the question that entitles this article.

Answer #1:  Because we bear this striking fact in mind – baptism is a sacrament and sacraments are not a new covenant novelty.  Indeed, the new covenant sacraments (baptism and communion) are rooted in the sacraments of the old covenant (circumcision and the Passover) and are to be understood according to their institution.  Regarding the latter the Old Testament offers no standard chronology for faith and circumcision.   For example Abraham was circumcised after he verbally professed faith (Gen. 17:22–27), but Isaac, Abraham’s son, was circumcised before his confession (21:4).  Yes, faith in the Lord was necessary in both of their cases.  Faith in the Lord was needed to appropriate all the benefits and blessings that circumcision promised, but the administration of circumcision as the sign and seal of those promised blessings was not tied to the timing of these men’s faith.  Because the New Testament links circumcision to baptism (Col. 2:8–15), Paedobaptists conclude that baptism, like circumcision, does not need to be tied to the timing of one’s profession of faith.

 
Answer #2:  We believe that the new covenant was foreshadowed by the old covenant and many of the principles of the old covenant still apply to the new.  One of these principles embraced by Paedobaptists concerns the fact that in the old covenant era God’s promises were given not just to adults but also to their children.  This reality was powerfully depicted in the Old Testament sacrament of circumcision.  Paedobaptists argue that it is hard to imagine that the far greater new covenant promises that we enjoy today in Christ should not also be given to the infant children of believing adults.  Such a diminishing of promised blessing seems even harder to imagine when one reads the Apostle Peter telling his audience on the day of Pentecost that the new covenant promises, like the old, are gifts for both believers and their children. (Acts 2:38–39).  Also there’s the odd fact that over a quarter of all baptisms recorded in the New Testament are of entire households.  Though it is admittedly an argument from silence can we reasonably assume that not one of these entire households had infants and/or small children in them?  Paedobaptists believe that such an assumption would be unreasonable.

​ 
 
Answer #3:  We Paedobaptists take seriously the New Testament’s clear teaching that the children of believing parents are set apart unto God (1 Cor. 7:12–14).   Under the old covenant it was circumcision that visibly set the children of believers apart from the rest of the world.  Paedobaptists believe that God, in the new covenant, still sets the children of believing parents apart from the rest of the world, marking them out as part of the visible community of God’s people through the waters of baptism.  Now it may be that my Credobaptists friends would object to this by pointing out that baptizing infants who lack personal faith in Christ is a worthless enterprise, but Paedobaptists would argue otherwise.  On the one hand it is very true that ultimately baptism without personal faith avails nothing. But on the other hand, the baptism of infants is far from worthless.  By the grace of God baptism marks out the children of believing parents as being really and truly part of the visible church, as heirs to all of the promises of God in Christ, and therefore responsible to embrace those promises by laying hold of Christ by faith as they grow in years and understanding.
 
In conclusion, “why do you baptize infants?”  Here’s why.  We believe that Paedobaptism is a beautiful and biblically defensible practice.  We also believe that the children of Christian parents have a particular relationship to the Lord that the children of unbelievers do not possess (1 Corinthians 7:12–14).  Furthermore, we believe that the children of believing parents have been sovereignly brought into the visible church by virtue of their natural birth and that unlike other children they will grow-up surrounded by the means of grace and fed upon the Word of God. 
 
To state it as simply as possible we baptize infants because we believe that they are part of God’s Kingdom too.   ​

In 13th century Norway there was something of a crisis brewing.  For some reason or other there was very little water available and many were fearful that they would run out altogether.  It seems, however, that what these Norwegians lacked in water they more than made up for in beer.  Barrel upon barrel of the stuff seemed to be everywhere – so much so that the local clergy promptly decided to put this surplus supply of suds to work for the Kingdom of God.

“Water is scarce,” they reasoned.  “Beer is not….  Why not baptize people with beer?”

Amazingly this thickheaded idea caught on and the practice spread from one parish to another until eventually Pope Gregory IX  caught wind of these brown bottle baptisms.  He found them difficult to swallow.  What followed was a spirited letter to the Archbishop of Trondhjem.  The letter was less than friendly, in fact it was a cold one.  In it Gregory stated his belief that baptism by brewski was baseless and therefore any such alcoholic ablutions were not authentic.

 To quote from Gregory IX’s letter:

 “Since according to the Gospel teaching, a man must be born again of water and the Holy Ghost, those are not to be considered validly baptized who have been baptized with beer.”

Thus the laver and the lager were forever separated.  Even today Pope Gregory IX’s edict is observed by both Roman Catholics and Protestants with a good deal of sobriety. 

In my own experience I have heard church leaders say things like:
​

“Unbelievers don’t know or understand hymns or metrical psalms – so let’s ignore these things!”


 “Unbelievers don’t understand the Bible – so let’s either keep our readings brief or avoid the book altogether!”


 “Unbelievers are uncomfortable with lengthy public prayers – we’ll keep them short!”


 “Unbelievers are suspicious of preaching – so let’s make sermons short and ‘relevant.’  We’ll talk about … say… hot-       button political issues, heartache, self-improvement, mere-morality, or the challenges of raising teenagers.”

​And so the mistakes continue to multiply until the final product is as strange as my Mc Fillet O’ Chicken.

So how do we correct this?

By starting in the right place – with the first component of worship.

What is it?

Simply this; we must believe that Lord’s Day worship is not about unbelievers.  It’s not about their wants, their musical tastes, their felt-needs, or anything else.  Lord’s day worship is about God, His wants, His commands, His requirements.  The concern of the worship of the Church is to please the Lord of the Church – our Faithful God who has taken great pains to reveal Himself in His Word.  Our prayers, our praise – every element of our worship services – must be in accordance with the Scriptures.  Above all the Word of God must be faithfully preached as the climatic act of public worship.  Why?  Because in faithful, expository preaching the Triune God of the Universe condescends to speak to His people.             

Yes!  Let the unbelievers in the door each Sunday!   By all means, compel them to come in!  But when they do, ensure that they get a glimpse of the glory of our God, a fearful understanding of His might, and a grasp of His wonderful grace in Christ Jesus.  Whatever we do, let’s not stroke the affections of unbelievers, let’s not try our best to put them at ease, let’s not say to them through word or deed, “Now we know that you’re not interested in Christianity or the church so we have something else for you today.”  No!  The fact is, we DO NOT have anything else for them.  If they don’t want our Savior who are we to suggest to them ways of spicing up their marriage?  If they won’t hear our gospel who are we to offer them rules of conduct to make their jobs more satisfying?  At the end of the day, all we have to offer them is a Prophet to teach them, a Lamb to take away their guilt, and a Shepherd-King to guide and protect them.  In a word, all we have to offer them is the One we gather to worship each Lord’s Day – and He is enough.  Yes, of course, we want our worship to be marked by intelligibility and clarity.  But no!  We do not want our worship to feel casual or “normal” to the unbeliever.  Because what happens Lord’s Day by Lord’s Day is anything but “normal.”  The great covenant making God is condescending to meet with His people once more in a special way.  He is meeting with them around Word and Sacrament.  He is renewing His covenant with them.  Here is the Triune God in the midst of a people once dead in trespasses and sins who He has raised to newness of life.   Here is the Triune God calling His people together and graciously giving the unbelieving world yet another sign that the Kingdom of God has indeed come.  This is anything but “normal” and cannot truly be conducted casually if it is to have the ring of authenticity about it

 As British pastor Geoffrey Thomas wrote in and article entitled Goat-Sensitive Worship:

            “If the style and mode of our expression when we meet in God’s presence is just like that which the goats hear in the office or in the schoolyard life then we have failed them. We whom the Lord is seeking and saving are sensitive to their real needs... So our worship will be simple, spiritual, substantial, warm, reverent, characterized by free prayer, great hymns and metrical psalms climaxed in expository preaching and anchored in proven forms that quickly gain familiarity and so become better means of channeling people to the God we are serving, and away from noticing clever servants who are speaking.”

By the way, when I realized my Mc Fillet O’ Chicken was all wrong I exchanged it for a proper one.  I would urge you by God’s grace to do the same.