OF AGE TO KNOW
To start off with, there is one factor that needs be acknowledged regarding the children of believing Parents.
Some children believe at a young age. And that's a marvellous thing. It arises from being in a godly family and among Believers and encountering God's word.
However, they have yet to possess the adult level of understanding, personal responsibility and accountability which repentance, faith, immersion in water, the Lord's Supper, etc, all require.
The person who has truly received Christ and possesses these things is "of age". They are able to speak for himself or herself understand what they are doing and take responsibility.
Being of age is crucial to a Believer's spiritual growth. It's then they possess the New Covenant Kingdom understandings of being immersed in water.
The Lord has provided some "of age" examples:
The young Mary has to be the first. Her faith, worship and understanding was acknowledged by the angel's greeting: "Rejoice, highly favoured one, the Lord is with you," Luke 1'28.
He added: "Do not be afraid, Mary, for you have found favour with God," Luke 1'30.
How did she find favour with God? Like her famous forebear, Abraham, she believed God's word. And it was accounted to her for righteousness, as it was him!
She was at the stage, personally and spiritually, to accept this commission and face the challenges of her immediate future, Luke 1'26-39.
Showing her trust in God she responded to the angel's statement:
"Behold the maidservant of the Lord! Let it be to me according to your word".
Mary was "of age" indeed!
A Jewish couple made it very clear that their son was of age! Almost all of John chapter nine is taken up with the incident that caused them to speak out.
They were being called on by Pharisees to take parental responsibility for what he said and did after Jesus had healed him of blindness. But they refused.
They were not willing to take the consequences for the strong way their son was rebutting the Pharisees' threatening questions.
They said: "He is of age; ask him. He will speak for himself"! Their son spoke for himself confidently and clearly, refusing to back down. His conduct revealed that he was of age!
Timothy is another example. Paul describes him as "a certain disciple" and the son of a believing Jewish woman and unbelieving Greek father and was well spoken of.
At one stage Paul called on him to be circumcised because of the Jews in that region who knew that his father was Greek (Acts 16'-1). Timothy understood Paul's concern and willingly yielded himself to it.
He had known the Scriptures from childhood which, Paul said, "... are able to make you wise for salvation through faith which is in Christ Jesus," 2 Timothy 3'15.
Later, as a believing young man, he was called to be an example to all:
"Let no one despise your youth, but be an example to the believers in word, in conduct, in love, in spirit, in faith, in purity," 1 Timothy 4'12.
About Moses being of age Hebrews 11'24-27 NKJV says:
"By faith Moses, when he became of age
refused to be called the son of Pharaoh’s daughter,
choosing rather to suffer affliction with the people of God
than to enjoy the passing pleasures of sin,
esteeming the reproach of Christ greater riches than the treasures in Egypt;
for he looked to the reward.
By faith he forsook Egypt, not fearing the wrath of the king;
for he endured as seeing Him who is invisible," Hebrews 11'24-27.
Although Moses may not have been as young as the healed man, or Mary or Timothy when he became of age the basics are the same.
So, those who desire to be Immersed in Water, and who desire to participate in the Lord's Supper, should be of age in order to rightly carry out these commands of Jesus, as these examples show.