Faith and Infant Baptism in Augustine and Aquinas

The historical evidence shows that infant baptism was regularly practiced from at least the 3^rd or 4^th century until the present day. One of the topics of discussion in the early church was how baptism could be an expression of faith when infants are not capable of expressing their own faith.

Of particular importance in this discussion was Augustine, who is well known for being the most influential theological figure of that time. In Augustine’s discussion of baptism, after having explained that baptism belongs to those who repent of their sins, Augustine addresses the obvious problem of what are infants repenting?

“Now, inasmuch as infants are not held bound by any sins of their own actual life, it is the guilt of original sin which is healed in them by the grace of Him who saves them by the laver of regeneration.”^[1]

In other words, although infants do not have any sins they themselves have committed, they must repent of original sin which is passed down through Adam. Obviously someone could raise the objection that it is not really repentance if infants have no ability to confess and forsake sin on their own. To this Augustine replies,

Some one will say: How then are mere infants called to repentance? How can such as they repent of anything? The answer to this is: If they must not be called penitents because they have not the sense of repenting, neither must they be called believers, because they likewise have not the sense of believing. But if they are rightly called believers, because they in a certain sense profess faith by the words of their parents, why are they not also held to be before that penitents when they are shown to renounce the devil and this world by the profession again of the same parents?^[2]

Augustine’s Alien Faith

We must take careful note of Augustine’s point here. His argument presumes the necessity of belief and repentance in baptism, but since the child is incapable, Augustine argues the parent’s words of faith and penitence are attributed to the child. Theologically this phenomenon is called fides aliena, a faith of others.^[3]

However, this concept of fides aliena prompted some significant debate. Although the problem of the infant having faith is resolved, a difficult question arises in its place—who is it that believes on behalf of the infant? The logical dilemma is brought forward as follows:

If fides aliena solves the problem of the infant’s lack of faith, it opens up a new question: who actually does the believing? The early scholastics reckoned with the possibility that parents or sponsors may not really believe. In this case, the act of believing devolves upon the church as a whole, as Augustine had said.^[4] But what if the entire church was in error? Then, said the early scholastics, it is the faith of the ecclesia triumphans, the church already in heaven, that suffices. But the church triumphant does not need faith; how can it “believe”? Answer: its faith is on deposit in the treasury of merits. So the theologians spun out the strands that came from the Pandora’s box that Augustine had opened.^[5]

An Infused Faith

The unsatisfactory theological consequences of Augustine’s fides aliena led to the Catholic development of fides infusa baptisme, a special “virtue or power infused by baptism.”^[6] Continuing with the idea that faith and baptism must be related, medieval thinkers like Peter Lombard proposed that the church conferred faith on the infant through the act of baptism.^[7]

Even renown Catholic theologian, Thomas Aquinas jumped into this debate. In his Summa Theologiae, Aquinas relied on Augustine, arguing that, “So that children believe, not by their own act, but by the faith of the Church, which is applied to them: by the power of which faith, grace and virtues are bestowed on them” (Summa Theologiae, Q 69, A 6). 

Although fides infusa became a dominant view in the Catholic church, like its predecessor fides aliena it suffers from an obvious dilemma. If the New Testament teaches faith is a prerequisite for baptism, then “faith cannot be both the prerequisite for baptism and the gift bestowed by baptism.”^[8]

It is not my goal in this post to evaluate the development of Catholic theology, or necessarily critique it. Rather, I want to make the simple point that from Augustine through the medieval period the unanimous opinion was that faith and baptism were somehow related. Although the exercise of volitional faith prior to baptism was easily accounted for in adult converts, the relationship of faith and infant baptism was heavily debated and led to two prevailing views—neither of which denied the relationship between faith and baptism, only tried to make sense of it. In contrast to the historical understanding of infant baptism and faith, in Reformed paedobaptist circles most proponents argue strongly that baptism has nothing to do with faith.

^[1] Augustine of Hippo, “A Treatise on the Merits and Forgiveness of Sins, and on the Baptism of Infants,” in Saint Augustin: Anti-Pelagian Writings, ed. Philip Schaff, trans. Peter Holmes, vol. 5, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, First Series (New York: Christian Literature Company, 1887), 24.

^[2] Augustine of Hippo, “A Treatise on the Merits and Forgiveness of Sins, and on the Baptism of Infants,” in Saint Augustin: Anti-Pelagian Writings, ed. Philip Schaff, trans. Peter Holmes, vol. 5, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, First Series (New York: Christian Literature Company, 1887), 24.

[3] Elsewhere Augustine notes that this principle only applies to infants. Cf. Augustine of Hippo, “On Baptism, against the Donatists,” in St. Augustin: The Writings against the Manichaeans and against the Donatists, ed. Philip Schaff, trans. J. R. King, vol. 4, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, First Series (Buffalo, NY: Christian Literature Company, 1887), 462. “Therefore, when others take the vows for [infants], that the celebration of the sacrament may be complete in their behalf, it is unquestionably of avail for their dedication to God, because they cannot answer for themselves. But if another were to answer for one who could answer for himself, it would not be of the same avail. In accordance with which rule, we find in the gospel what strikes every one as natural when he reads it, ‘He is of age, he shall speak for himself.’”

[4] Augustine of Hippo, “A Treatise on the Merits and Forgiveness of Sins, and on the Baptism of Infants,” in Saint Augustin: Anti-Pelagian Writings, ed. Philip Schaff, trans. Peter Holmes, vol. 5, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, First Series (New York: Christian Literature Company, 1887), 30. “And that this takes place in the case of infants, through the sacrament of baptism, is not doubted by mother Church, which uses for them the heart and mouth of a mother, that they may be imbued with the sacred mysteries, seeing that they cannot as yet with their own heart ‘believe unto righteousness,’ nor with their own mouth make ‘confession unto salvation.’

[5] Jonathan H. Rainbow, “‘Confessor Baptism’: The Baptismal Doctrine of the Early Anabaptists,” in Believer’s Baptism: Sign of the New Covenant in Christ, ed. Thomas R. Schreiner and Shawn D. Wright, NAC Studies in Bible & Theology (Nashville, TN: B & H Academic, 2006), 191.

[6] Rainbow, “‘Confessor Baptism’: The Baptismal Doctrine of the Early Anabaptists,” 191.

[7] Rainbow, “‘Confessor Baptism’: The Baptismal Doctrine of the Early Anabaptists,” 191. Rainbow cites A. M. Landgraf, Dogmengeschichte der Frühscholastik, Dritter Teil: Die Lehre von den Sakramenten (Regensburg: Verlag Friedrich Pustet, 1954), 323, as a scholar who claims fides infusa was the “distinctive contribution” of scholastic thought concerning the relationship between faith and baptism.

[8] Rainbow, “‘Confessor Baptism’: The Baptismal Doctrine of the Early Anabaptists,” 191.