Except that the adult entered into the covenant knowingly... A covenant, in modern terms, is called a contract - who believes that a contract made with an infant is binding?
This is one area where to me the reformed perspective answers these questions most satisfactorily.
God, from before the foundation of the world, ordained the names of His family, all believing Jews and Gentiles. At a time of His choosing, God will send the Holy Spirit to each of His children who will regenerate their life, give them new ears and new eyes, a heart of flesh and a renewed mind, all to know the things of God and believe to the saving of their soul.
Accepted, and that gratefully, with the exception that predestination is inclusive rather than exclusive - Christ is seen blotting names out, not writing them in. It seems to be a small exception, but it has major ramifications. The Father would that all of Adam's sons be saved. Every one.
Infant baptism acknowledges this fact.
Only if it is exclusive (which I do not believe).
The covenant of salvation began at the same moment God ordained the life and death and resurrection of the Lamb slain from the foundation of the world, first made known to us according to the Law of Moses (to show us that none of us can keep the Law perfectly) and then mercifully revealed to us by Christ on the cross, according to the covenant of grace.
And from my reading of Scripture, children in both the OT and NT testaments were included in the covenant, the "promise" having been made to all believers and their children, "as many as the Lord our God shall call."
"as many as YHWH will call" being the operative phrase... Are all entered into the covenant then, or only those who are truly saved? Constantine baptized his entire army into Christ, as they were ordered to march through the waters. Have they in fact entered into the covenant or not?
How then is an infant any different than one of Constantine's soldiers? There is no repentance... How can there be grace?
Where once believers were of one nation and their children were circumcised in the flesh, believers now come from all nations and they and their children are circumcised of the heart.
Ahhh.. there, then, is the problem: What is the circumcision of the heart? The "circumcision made without hands"?
It's a wonderful blessing to know that God has given us our children and that He will guide them throughout their lives. Do some stumble and fall away? Probably. Who knows for certain?
If they fall away, then they never belonged to Him at all, for none can take us from His hand.
But knowing that our children belong to Him makes the Christian family stronger and each of us more determined to raise our children to kneel to none but Christ.
I pray for my children every day, that they will come to find the Father, as I did, and I remind Him of His promises. Do I raise them up in His ways? To the best of my abilities, sure I do... But I have no control over their personal decisions - That is between them and the Father. I have done/am doing all that I can.
It’s becoming very obvious that you think that it’s baptism that saves not Jesus sacrifice on the cross. Your obsession with baptism is the least of your problems.
Is it the Book of Life where your name is written, or the Book of Death where your name is crossed out?
God wrote the Book of Life and it is indelible. That's good news, Christian.
How then is an infant any different than one of Constantine's soldiers? There is no repentance... How can there be grace?
Because grace precedes repentance. Grace before all else.
But I have no control over their personal decisions - That is between them and the Father.
Exactly. Therefore thank God He has control over those decisions. If not, we'd all be sunk.