MATURITY

John 1:12 But as many as received Him, to them He gave the right to become children of God, even to those who believe in His name:
When you receive JESUS YOU have the right to be his child that is the first step that many Christians have already done.

Many people are children of God. but to be children of God it the starting point you have now to grow up to be sons of God . Paul says in
Romans 8:14
For all who are led by the Spirit of God are sons of God.

Here Paul explained the difference between being a child&son of God ,to be a son of God here means being Fully developed; grown in terms of behaviour , spiritually; being muture. according to Paul u will be mature o only when you are being led by the Spirit of God himself.

Isa 9:6 For unto us a Child is born, unto us a Son is given; and the government will be upon His shoulder...
You noticed with me that it says a child is born but a son is given which means the child JESUS was born from Marie but a mature (son)was given through the Holy Spirit