Why do you baptize babies since there is no biblical reference to infant baptism? Only those who had received the Holy Ghost were baptized. Is it for the purpose of dedication?
You seem to agree with the Reformed and Presbyterian Christians that biblical Baptists baptize (formerly) pagan adults who are new converts when they are ready to publicly profess Christ to be the only Savior of sinners and to be their Savior.
Note also, however, that in Acts 10 and in Acts 16 whole households were baptized and that is the same thing that was done in Genesis 17 where the Lord our God ordered Abraham to give the church visible form, and to take a step of commitment in the covenant of grace by circumcising all the males in his household, young and old, servants and slaves. This included Ishmael, whom God passed by as heir of the covenant promises.
Everybody who believes the Bible admits that God commanded circumcision to be done on the eighth day to the male infants of covenant-keepers (see Gen. 17:12).
Genesis 12, 15, and 17 are important background to the New Testament. First, note that the virgin Mary, Zacharias, the first three sermons in Acts (Acts 2, 3, and 7), the apostle Paul in Romans and Galatians, and James all appeal to the covenant that God made with Abraham, saying the Lord our God is remembering it and it is being fulfilled with the coming of the Messiah (God the Son incarnate) and the pouring out of the Holy Spirit. The promise is to us and to our children.
Although Jesus changed circumcision to baptism in the great commission, he did not change the claims of truth and righteousness. Nor did he change the needs of sinners for the Holy Spirit, or for repentance and faith. Jesus' great commission presses these claims upon all ages. So did the apostle Peter in Acts 2, 3, and 10.
The New Testament does not know anything about infants not being accountable, or having to grow up a decade or more before they reach a supposed "age of accountability." In order to preach Jesus, the New Testament speakers all appeal to the Old Testament to adequately set forth the identity of Jesus and what the church should do. The three major changes in the New Testament church from the Old Testament Church (Acts 7:38; the Greek reads ekklesia—church—not congregation) do not change the doctrine, the form of church government, or the synagogue worship as brought into the New Testament Church.
What did change is this:
These were all changed by Jesus. Yet, Jesus nowhere said, "Exclude the infants, for of such is not the kingdom of God. You must become as adults before I will give the Holy Spirit or repentance for sins, or saving faith." In fact Luke 18:15-17 says just the opposite.
Baptism is not man's testimony or sign of what he the man has done. Baptism is God's testimony to man of what God does, when and where he pleases, to wash sinners from the filth and guilt of their sins. Baptism is God pointing down to man and declaring the gospel. Baptism is not man pointing up to God with a message, nor man pointing to himself and giving out a message.
If you go back and read about those household baptisms in Acts 10 and 16, it takes imagination and wishful thinking to hold that infants were not baptized by Peter. The apostle Peter had more covenant consciousness of the head of the family being the spiritual head of the household than some people of today have.
The Heidelberg Catechism of 1563 gave the following answer to your question. I strongly recommend that you study the scriptural citations they give in support. Although I used a different line of argument above in this letter, I in no way deny the Heidelberg Catechism, Q. 74, or disagree with it. I love its answer.
Q. 74. Are infants also to be baptized?
A. 74. Yes, for since they, as well as their parents, belong to the covenant and people of God, and through the blood of Christ  both redemption from sin and the Holy Ghost, who works faith, are promised to them no less than to their parents, they are also by Baptism, as a sign of the covenant, to be ingrafted into the Christian Church, and distinguished from the children of unbelievers, as was done in the Old Testament by circumcision, in place of which in the New Testament Baptism is appointed.
1. Gen. 17:7
2. Matt. 19:14
3. Luke 1:14-15; Psa. 22:10; Acts 2:39
4. Acts 10:47
5. Gen. 17:14
6. Col. 2:11-13
If you want to ask further questions, I would be glad to try to answer them.
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