How does one go about defending infant baptism scripturally?
This is my grandmother (independant baptist) who proclaims it invalid, so the argument needs to be solid and meaty.
Old Covenant
Genesis 17:9-14
9 Then God said to Abraham, “As for you, you must keep my covenant, you and your descendants after you for the generations to come. 10 This is my covenant with you and your descendants after you, the covenant you are to keep: Every male among you shall be circumcised. 11 You are to undergo circumcision, and it will be the sign of the covenant between me and you. 12 For the generations to come every male among you who is eight days old must be circumcised, including those born in your household or bought with money from a foreigner—those who are not your offspring. 13 Whether born in your household or bought with your money, they must be circumcised. My covenant in your flesh is to be an everlasting covenant. 14 Any uncircumcised male, who has not been circumcised in the flesh, will be cut off from his people; he has broken my covenant.”
Leviticus 12:3
3 On the eighth day the boy is to be circumcised.
These texts show the circumcision of eight-day-old babies as the way of entering into the Old Covenant.
Connection to New Covenant
Col 2:11-12
11In him you were also circumcised, in the putting off of the sinful nature,
a] not with a circumcision done by the hands of men but with the circumcision done by Christ, 12having been buried with him in baptism and raised with him through your faith in the power of God, who raised him from the dead.
Baptism is the new “circumcision” for all people of the New Covenant.
Do Infants Need Baptism?
Job 14:1-4
1 "Man born of woman is of few days and full of trouble. 2 He springs up like a flower and withers away; like a fleeting shadow, he does not endure. 3 Do you fix your eye on such a one? Will you bring him before you for judgment? 4 Who can bring what is pure from the impure? No one!
Psalm 51:5
5 Surely I was sinful at birth, sinful from the time my mother conceived me.
We are conceived in the iniquity of sin. This shows the need for baptism from the moment of conception.
Jesus Extols Child-like Faith
Matthew 18:2-5
2He called a little child and had him stand among them. 3And he said: "I tell you the truth, unless you change and become like little children, you will never enter the kingdom of heaven. 4Therefore, whoever humbles himself like this child is the greatest in the kingdom of heaven.
Jesus says unless we become like children, we cannot enter into heaven. **So why would children be excluded from baptism? **
Jesus Receives Little Children and Infants
Matt 19:13-15
13Then little children were brought to Jesus for him to place his hands on them and pray for them. But the disciples rebuked those who brought them. 14 Jesus said, “Let the little children come to me, and do not hinder them, for the kingdom of heaven belongs to such as these.” 15 When he had placed his hands on them, he went on from there.
Mark 10:13-16
13People were bringing little children to Jesus to have him touch them, but the disciples rebuked them. 14When Jesus saw this, he was indignant. He said to them, “Let the little children come to me, and do not hinder them, for the kingdom of God belongs to such as these. 15I tell you the truth, anyone who will not receive the kingdom of God like a little child will never enter it.” 16And he took the children in his arms, put his hands on them and blessed them.
**Jesus says to let the children come to Him for the kingdom of God also belongs to them. There is no age limit on entering the kingdom, and no age limit for being eligible for baptism. **
(cont.)