The Loss of Infants: What is their Destiny?

What comfort can we offer to parents whose infant dies in infancy? And what is the real tragedy of abortion?
Reformed Confessions have spoken to this issue, Charles Spurgeon has addressed the question, B.B. Warfield has as well, and many of us have some view on what happens to infants dying in infancy or babies that are mercilessly slaughtered in their mother's womb. But there is no clear unanimity from Christian theologians over the centuries.
Preaching on 2 Kings 4:26, Spurgeon made this comment:
"As for modern Calvinists, I know of no exception, but we all hope and believe that all persons dying in infancy are elect."
Some of the exegesis and theology that has been used to defend the idea that all infants dying in infancy are saved has not always been biblically sound. In addition, a type of sentimentalism can enter into our thinking that isn't actually grounded in God's Word or his character. 
The Reformed doctrine of original sin, which usually includes imputed guilt, essentially means that there is no such thing as an innocent child in the eyes of God. All infants are guilty and corrupt before God, at conception, because of original sin (Rom. 5:12ff; Job 14:4; 15:14; Ps. 51:5). Those who go to hell are not there simply because of what they did, but because of who they are: they are sinners who have not been covered by the blood of Christ. Their identity remained "in Adam" (who they are) and so they have acted in accordance with that identity (what they have done). Because of original sin, and all that means, there really is no "age of accountability." We miss the point if we ask, "When does a child first sin or become accountable?" (Which is why references to Rom. 1:20 do not really solve much in this debate).
Moreover, many appeal to the goodness/love of God as the chief reason for why all infants who die in infancy will go to heaven. But this truth about God's nature cannot be made into a wax nose so that we can do with this attribute whatever makes us feel comfortable. People have made similar arguments for universalism, annihilationism, and homosexual unions. A loving God, so the argument goes, would never do this or that or disapprove of this or that. Think about that argument and then read about the worldwide flood in Noah's time and what that would have meant for the many young children who were engulfed and drowned by the waters of judgment.
Whether we are comfortable with this truth or not, the Bible clearly distinguishes between the infants of believers and the infants of unbelievers, both in the Old and New Testaments. The children of believers are "holy" (clean) whereas the children of unbelievers are not "holy" but "unclean" (1 Cor. 7:14). This New Testament teaching continues the basic difference between Israelite children and the children of the surrounding nations in the Old Testament, who were unclean (also sometimes called "dogs", Matt. 15:26).
In Deuteronomy 20, God commands the destruction of (unclean) children (Deut. 20:16-17). Read also Joshua 6; read 1 Samuel 15. The destruction of these pagan children seems harsh, until we realize they would likely have grown up to engage in the "abominable practices" of their parents (see also Ps. 137:8-9; Isa. 11:16). The seed of every known sin is present in the heart of an infant. 
Some authors who address this topic seem to (perhaps conveniently) miss or ignore the biblical data that proves that God's love and goodness does not mean he will not command the destruction of children in certain contexts. There's a corporate solidarity - whether in community or family - in the Scriptures that is perhaps lost to a lot of us today or not fully appreciated.
With this in mind, I do not believe we can say that the infants of unbelievers will definitely go to hell. However, I do not believe, based on the above, that we can say they will definitely go to heaven. Personally, I am agnostic on that specific question. But I do not believe, contrary to some, that the biblical evidence requires us to say that all infants dying in infancy will go to heaven.
Nonetheless, we can speak more definitively to this issue when it comes to the children of believers.
The Canons of Dort address the topic better, and certainly more pastorally, than the Westminster Confession of Faith, in my view:
1st Head of Doctrine, Article 17. Since we are to judge of the will of God from his Word, which testifies that the children of believers are holy, not by nature, but in virtue of the covenant of grace, in which they, together with the parents, are comprehended, godly parents have no reason to doubt of the election and salvation of their children, whom it pleases God to call out of this life in their infancy.
The basis for having this hope is not merely the goodness of God, but the goodness of God as revealed in his covenantal promises towards his people. The children of believers are holy, and thus their identity is not, as far as we are to judge, "in Adam". They have been set apart, with a new identity (i.e., they are holy). The issue before us concerns the judgment of charity, not our ability to infallibly know the decree. God's Word seems to give us some grounds to make these judgments, which, as a pastor, I am glad to offer to bereaved parents in my congregation who have lost an infant.
In short, our identity (as justified children of the Father), not our works, is the primary basis for where we end up in eternity.
How does this relate to abortion?
The great tragedy of abortion is that it robs a child the privilege of hearing the gospel and being saved from this world of sin and misery. In the case of infants of unbelievers, this is especially tragic. Why?
Once we grasp that God could, based upon his righteous nature, and because infants are guilty in Adam (i.e., original sin), send these children to hell, we are faced with the true horror of abortion. Christians understand the eternal consequences involved in any human life. We have the greatest reasons to be against abortion.
Again, I am not saying that God sends the children of unbelieving parents to hell. But I am saying the Scriptures do not give us quite the grounds that some (e.g., Spurgeon) think for saying that he will certainly save all children dying infancy. This view, advocated by some, where all infants, regardless of whether they are the infants of believers or unbelievers, go to heaven when they die in infancy might lead to a sort of "happy guilt" (felix culpa) - 'abortion is bad, but at least they all go to heaven' type of attitude. However, since we can't know, the stakes are so very high, which is why we should aim to end abortion in order that we can aim to win these children to Christ.
The WCF (10.3) says, "elect infants, dying in infancy, are regenerated, and saved by Christ, through the Spirit..." - a view that could still allow for all infants, without exception, to receive salvation, but also allows that not all infants will necessarily be saved. Certainly the Westminster divines, based on the public directory for worship, which calls the children of believers "Christians", would have likely been in agreement with the Canons of Dort on this issue.
Pastors have grounds for giving real comfort to Christians who have to deal with the tragedy of losing a child, especially infants (see perhaps 2 Sam. 12:23, which involves a covenant child). I cannot offer that same comfort to an unbeliever. Yet, that doesn't mean an unbeliever's child cannot be elect. It only means that I do not have covenantal grounds for offering that comfort.
Those who do not see a covenantal difference between the infants of believers versus the infants of unbelievers have to maintain that there cannot be any difference between the child of a Muslim parent and the child of a Christian parent. That is why some seem to speak of "all infants" going to heaven without reference to a distinction between the children of believers versus unbelievers. In one respect, I find this view appealing for many reasons, but I have to admit that it may not enjoy quite the biblical support that is needed.

Naturally, there are many other questions that arise when this issue is discussed. Yet, regardless of where we stand on this issue, and I do believe there are important practical consequences for what we believe, we certainly can all say: "will not the judge of all the earth do what is right?" (Gen. 18:25)