The Scriptural model is not explicit when referring to infant baptism. In the NT, whole households were baptized - not whole households minus the infants - and so therefore there is precedence.
It is the development of the Church that the infant model needed to be taken to the point where the necessity of baptism be given to all as soon as is practicable, and yet have that requirement that belief be in place. Thus, the split in the Church between the moment of baptism and the acknowledgement of those mature enough to be able to confirm that they are willing to be baptized.
You must remember that Jesus left us His Church; that Church is the teaching institution and there is no other outside of private revelation of the Holy Spirit. We examine the proofs of private revelation in order to determine their accuracy or even origin, but we are subordinate to the Holy Spirit. We have not made God in our own image, as is the apparent practice of many Protestants, especially the Calvinists.
No, I must remember that Jesus left us the Holy Spirit and the Scriptures so any church making claims of exclusivity can be easily rebutted and upside down doctrines such as two stage baptism can be seen for what they are.