“If there is but one unchanging God, one way of salvation, one faith, one church, one (spiritual) baptism, and one spiritual meat and drink (1 Cor. 10) in both testaments, the sacraments of both testaments must bear the same spiritual significance. Only their signs differ. And if both the two testaments and their sacraments are substantially one, there is no good reason to withhold baptism from Christian infants. They do not at their age believe, but then neither did the infants of the Old Testament Jew, who were beneficiaries of both the sign of the covenant and its full blessing.”
Taken from Lyle D. Bierma’s book titled The Covenant Theology of Caspar Olevianus (39-40)
Bierma here is summarizing Olevian’s position on infant baptism.