Conviction before Regeneration

"The conviction of the Spirit mediately prepares sinners for faith.

The critically important role of the convicting work of the Spirit was announced by Christ in John 16:8-11. We should view this as preparing the heart for faith and regeneration by breaking through the spiritual death and blindness which obstruct faith. This helps to explain how any spiritually dead sinner can come to saving repentant faith in Christ. We can best understand the ministry of the “other paraclete (from the Greek paraklçtos; one who entreats, encourages, exhorts)” by noting the parallel with the first paraclete, Christ Himself. He most effectively used the Mosaic Law to bring about conviction of sin.

Since Christ predicted the coming of the Spirit on the day of Pentecost, the events in Acts 2 are the first example of the conviction of the Spirit as promised by Christ. The Holy Spirit, the divine Advocate, used Peter to charge the nation with the sin of crucifying Christ, and as a result, they were “pierced to the heart” and cried out, “Brethren, what shall we do?” They were under conviction but had not yet repented as seen in Peter’s response to, “Repent!” As the word of God is preached the Holy Spirit uses the word and brings some people under conviction. But not all who are brought under conviction ultimately repent and turn toward Christ." ("Mediate Theology - 12 Supporting Propositions" by Dr. C. Gordon Olson)

http://www.mediatetheology.org/uploads/Twelve_Supporting_Propositions.pdf