Nobody by nature delights so much in the character of God that he hungers after the true God. We are by nature children of wrath (Ephesians 2:3). As David said in Psalm 51:5, “Behold, I was brought forth in iniquity and in sin did my mother conceive me.” We come into the world bent on being independent from God and loving the things of the world. Something has to happen to us if we are to be saved from the wrath of God (1 Thessalonians 1:10). We must be profoundly changed. - John Piper

For the full text this quote was take from please visit this link. A very good explanation of the Holy Spirits work in conversion.