What follows is a list of quotes from the early fathers which shows very clearly that not baptizing infants was a newer change in church history. The prevailing, standard, widespread practice was to baptize infants:
INFANT BAPTISM - HISTORICAL SUPPORT
For historical support of infant baptism, note the following sources:
Eighty and six years have I served Him.1 Polycarp (69-156 AD)
And many, both men and women, who have been Christ's disciples from childhood, remain pure at the age of sixty or seventy years.2 Justin Martyr (100-165 AD)
[Jesus] came to save all through the means of himself-all, I say, who through him are born again to God-infants, and children, and boys, and youths, and old men.3 Irenaeus (c. 130-200 AD)
And so, according to the circumstances and disposition, and even age, of each individual, the delay of baptism is preferable; principally, however, in the case of little children. . . . Let them become Christians [i.e. in baptism] when they have become able to know Christ.4 Tertullian, (155/160-220/230 AD) De Baptismo, in which he speaks against infant baptism. His opposition would seem to indicate that it was standard practice at the time.
First you should baptize the little ones. All who can speak for themselves should speak. But for those who cannot speak, their parents should speak, or another who belongs to their family. Then baptize the grown men, lastly the women.5 Hippolytus (170-235 AD)
Infants are baptized for the forgiveness of sins.6 Origen (185-254 AD)
The church received from the apostles the tradition to give even little children to baptism.7 Origen
But in respect of the case of the infants, which you say ought not to be baptized within the second or third day after birth, and that the law of ancient circumcision should be regarded, so that you think that one who is just born should not be baptized or sanctified within the eighth day, we all thought very differently in our council. . we all judge that mercy and grace of God is not to be refused to any one born of man. . . . Moreover, belief in divine Scripture declares to us, that among all, whether infants or those who are older, there is the same equality of the divine gift. Age may have a difference in the increase of our bodies, according to the world, but not according to God.8 Cyprian (200-258 AD)
Augustine, (354-430 AD) De Baptismo Contra Donatistas, 4, says in regard to the baptism of small children that the church universal holds to this, and it has not been established by councils but has always been held and handed down by apostolic authority [and] is most correctly believed.9 Chemnitz, Loci, II, p. 727
1 Roberts and Donaldson, The Ante-Nicene Fathers, Vol. 1, p.41
2 Roberts and Donaldson, The Ante-Nicene Fathers, Vol. 1, p. 167 (15, 6).
3 Alexander Roberts and James Donaldson, Ed., The Ante-Nicene Fathers, (Grand Rapids: Eerdmans, 1885, Reprinted 1973), p. 391 (4, 7-9).
4 Roberts and Donaldson, The Ante-Nicene Fathers, Vol. 3, p. 678.
5 Burton Scott Easton, The Apostolic Tradition of Hippolytus, (Archon Books, 1962), p. 45 (XXI, 3,4).
6 Samuel Miller, Infant Baptism Scriptural and Reasonable, (from Origen's Homily 8 on Leviticus 12), http://www.swrb.com/newslett/actualnls/baptism3.htm
7 Samuel Miller, Infant Baptism Scriptural and Reasonable, (from Origen's Commentary to the Epistle to the Romans, Lib. 5), http://www.swrb.com/newslett/actualnls/baptism3.htm
8 Roberts and Donaldson, The Ante-Nicene Fathers, Vol. 5, p. 354 (58).
9 Martin Chemnitz (translated by J. A. O. Preus), Loci Theologi, (St. Louis: Concordia Publishing House, 1989), Vol. 2, p. 727.
Likewise, here are some more citations from the fathers showing the widespread practice of baptizing infants:
History establishes the fact that infant baptism was practised in the early church.
a) Note the following testimonies.
-1) The Synod of Carthage (256?) discussed the question (raised by Bishop Fidus) if Baptism might properly be administered before the eighth day. The Synod answered in the affirmative: Grace may not legitimately be withheld from any one who has been born.
-2) Origen (+254) declares: Ecclesia ab apostolis traditionem suscepit etiam parvulis baptismum dare.
-3) Tertullian (+220) opposed infant baptism in a way which shows that it was then an established custom.
cf Cunctatio baptismi utilior est, praecipue tamen circa parvulos: 1. Ouid enim necesse ... sponsores etiam periculo ingeri? ... 2. Quid festinat innocens aetas ad remissionem peccatorum? (why bring the innocent of age to the remission of sins? literally)
-4) Irenaeus (+202; disciple of Polycarp, disciple of John): Omnes venit (Christus) per semet ipsum salvare; omnes, inquam, qui per eum renascuntur in Deum, infantes, et parvulos et pueros et juvenes et seniores.
-5) Justin Martyr's (~165) phrase: μαθητεύεσθαι ἐκ παίδων (cf. Mt 28:19) is most satisfactorily understood of Baptism (catechumenate?) particularly in view of the fact that he regards Baptism as the N.T. counterpart of O.T. circuncision.