The new birth!

(William Nicholson, "The Character and Dignity of Christians" 1862) 

"You have been born again, not of perishable seed, but of imperishable, through the living and abiding word of God!" 1 Peter 1:23

No one is born a Christian. No one comes into the world with a pure heart.

The new birth is not effected by baptism — yet some have wickedly declared that we are regenerated by baptism, made children of God, and heirs of the kingdom of Heaven. A person may be baptized in infancy, or in riper years — and yet, like Simon Magus, remain "in the gall of bitterness and in the bond of iniquity!" Acts 8:23

The new birth is not merely external, nor does it consist in mere religious duties. Some people have been preserved from immoralities, yet they too must be born again.
A man may perform a multitude of religious duties — and yet have an unholy heart.
He may be honest and fair in his dealings — and yet be an enemy to God.
He may be of a generous to others — and yet not of a gracious disposition.
He may be able to say with the young ruler, "All these things have I kept from my youth up," and yet lack the one thing needful.

The new birth is not merely a profession of faith. Not all who profess Christ, possess Him.

The new birth is a change wrought by the power of the Holy Spirit in the understanding, will, and affections of a sinner, which is the commencement of a new kind of life; and which gives another direction to his judgment, desires, pursuits, and conduct.

This new birth is a divine change. Thus He who gave man his physical being at first, can alone create him in Christ Jesus unto good works. He alone can enstamp His own image, and make us partakers of a Divine nature. To give life to the dead, and to bring a clean thing out of an unclean — is the work of Omnipotence, and the effect of sovereign grace! "Who were born, not of blood nor of the will of the flesh nor of the will of man, but of God!" John 1:13 

This new birth is an inward and invisible change.
The understanding is enlightened,
the judgment is informed,
the affections and desires are purified,
the will is subdued, and subjected to the will of God,
the soul is turned from the love of the world and the creature, to the great Creator and His service.
Regeneration cleanses the corrupt fountain of the heart, and demolishes the strongholds of Satan. It is a change . . .
  from heart wickedness — to heart holiness,
  from enmity to God — to love to God,
  from the image of Satan — to the image of God.

This new birth is a universal change, extending to the heart and life. Not only the mind — but the man is renewed. The tree is made good, and its fruit is good. "Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come!" 2 Corinthians 5:17

He who is born again, gives evidence that he has passed from death to life. It is visible in his conduct — the observer of him perceives the change. How different now, from what he once was! The following are the principal evidences of regeneration:
(1) Hatred to sin.
(2) Victory over the world.
(3) Brotherly love.
(4) Delight in spiritual duties.
(5) A life of holiness.
(6) Self-loathing, and constant faith in the sacrifice of Christ.
(7) Sincere love to Christ.