Charles Spurgeon Commentary John 1:12-13

"But as many as received him, to them gave he the right to become children of God, [even] to them that believe on his name: who were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God." — John 1:12-13 (ASV)

But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name: Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.

To receive Christ, one must be born of God. It is the simplest thing in all the world, one would think, to open the door of the heart, and let him in; but no one lets Christ into his heart till God has first made him to be born again, born from above.