"But when the High Priests and the Scribes saw the wonderful things that He had done and the children who were crying aloud in the Temple, "GOD SAVE THE SON OF DAVID," they were filled with indignation. "Do you hear," they asked Him, "what these children are saying?" "Yes," He replied; "have you never read, 'OUT OF THE MOUTHS OF INFANTS AND OF BABES AT THE BREAST THOU HAST BROUGHT FORTH THE PRAISE WHICH IS DUE'?"" (Matt. 21:15,16)
Infants may and do praise their God, as well as adults, according to His Word, not man's tradition nor rationale.
And it happened, as Elizabeth heard Mary's greeting, the babe in her womb leaped, and Elizabeth was filled of the Holy Spirit. And she cried out with a loud voice and said, You are being blessed among women and blessed is the fruit of your womb! And why is this to me that the mother of my Lord comes to me? For behold, as the sound of your greeting came to my ears, the babe in my womb leaped in exultation. And blessed is she believing, because there will be a completion to the things spoken to her from the Lord. And Mary said, My soul magnifies the Lord,and my spirit exulted in God My Savior. (Lk.1:41-47)
The spirit of both infant and adult may exult in God as Savior, or Yeshua God's Salvation, according to His Word, not man's tradition nor rationale.
“We see in this passage [Luke 1:39-44] that infants are capable both passively of being filled with the Holy Ghost and actively of responding with joy to the presence of Christ” (Revealed to Babes)
"The most mature believer does not so much apprehend Christ as he is apprehended by Christ (Philippians 3:12). It is not as important to the child of God what he knows of God as the fact that God knows him (Galatians 4:9). A covenant child is as capable of being apprehended and being known as is an adult." (Revealed to Babes)
Adults nor infants are capable of changing their own hearts...
But God, being rich in mercy, because of the intense love which He bestowed on us, caused us, dead though we were through our offences, to live with Christ--it is by grace that you have been saved-- raised us with Him from the dead, and enthroned us with Him in the heavenly realms as being in Christ Jesus, in order that, by His goodness to us in Christ Jesus, He might display in the Ages to come the transcendent riches of His grace. (Eph. 2:4-7)
1Co 7:14 "for the unbelieving husband hath been sanctified in the wife, and the unbelieving wife hath been sanctified in the husband; otherwise your children are unclean, but now they are holy.
Children of believers are baptized not that they may become holy but because they are holy."
In 1 Cor 7:14 the word holy which is used to describe the children of believers is the greek word hagios.
From Strongs ; sacred (physically pure, morally blameless or religious, ceremonially consecrated): - (most) holy (one, thing), saint.
It is used 231 times in the N.T. Translated 'holy' 168 times, 'saints' 60 times, 'most holy' once, 'saint' once, and saints' (plural posessive) once.
Children of believers are baptized in faith. That faith is in God, His Grace, His Salvation, His Promise. Act 2:39 "For the promise is to you, and to your children, and to all those afar off whom God will call."
Heb 11:1 Now faith is the persuasion of the things that are in hope, as if they were in act; and [it is] the manifestness of the things not seen.
Eph 2:8-10 For by grace you are saved, through faith, and this not of yourselves; it is the gift of God; not of works, that not anyone should boast; for we are His workmanship, created in Christ Jesus unto good works, which God before prepared that we should walk in them.
God's salvation is by God's Grace, and the faith of God's elect is His gift and not by decisional nor baptismal regeneration.
Quote from 'gotquestions' article, "If Christian parents wish to dedicate their child to Christ, then a baby dedication service is entirely appropriate."
Baby dedication as practiced today has no warrant from the Word. It is but man's substitute for God's ordinance of baptism.