The grace of God that comes to a person before the new birth to awaken and arrest him to unseen realities and causes him to see his sinfulness and helpless estate is sometimes call prevenient grace or preventing grace. This produces conviction for sin and a deep desire for God that can only be satisfied by an inward, startling revelation of Jesus Christ.
This inward revelation is accomplished by the Holy Spirit as a gift of salvation after the believe has gone through a pre-birth period (long or short) of preparation of the heart. This is shown clearly in the book of Acts. Devout men, some of whom were "accepted of God," were brought suddenly into a revelation of the Son of God by the Holy Ghost. This was the beginning of a new era; the start of the New Testament Church of Jesus Christ.
The New Testament in general teaches that ALL genuine Christians are consciously indwelt by the Holy Spirit and Christ is revealed to them by the Holy Spirit. The book of Acts shows this in experience and St. Paul writes the doctrine: "If any man have not the Spirit of Christ he is none of his" (Romans 8:9) and "For by one Spirit are we all baptized into one body... and have been ALL made to drink into one Spirit" (1 Corinthians 12:13). There are not REAL Christians without the Holy Spirit. This is what generates the Church.
The disciples of Jesus before Pentecost were not lost and were "accepted" of God, even as Cornelius. Jesus said, "None of them is lost" (John 17:12). The grace of God brought them into a new and better way which became possible only after Pentecost. This prevenient grace that led them preceded their understanding of the resurrection and the outpouring of the Holy Spirit. His grace is always previous. The Calvinists recognized this and called it election. They say that such men have saving grace when they feel these stirrings and leadings of the Holy Spirit. They deduct that because they believe in the historical Jesus and feel these leadings they are born again, when in reality they are only in a pre-New Testament experience. Many never know they can have a clear cut assurance of saving grace. In the holiness circles these same type of people are told to seek a "second blessing" or "get the Holy Ghost," when in reality they are not yet New Testament Christians.
This grace that awakens and convicts the sinner and causes him to abhor his sins, is sometimes accompanied by short seasons of love, joy, and peace long before saving faith is imparted.
This prevenient grace is seen in a number of places in the book of Acts. We find that on the day of Pentecost devout Jews from every nation under heaven (2:5) were awakened by the Spirit and they said, "What shall we do?" (2:37). These devout men were under prevenient grace before the day of Pentecost.
In Acts 8 we see the Ethiopian eunuch was moved by the Spirit to read Isaiah and Philip was led to join him in the Bible study.
In Acts 9 Saul is smitten by the Holy Spirit (without an altar call), three days before he was told to arise and be baptized and wash away his sins and receive the Holy Spirit, (thus becoming a New Testament Christian).
In Acts 10 we see the Holy Spirit working with devout Cornelius and causing Peter to go to him. Cornelius was not a New Testament Christian at this time, but was "accepted" because his faith in the unknown Christ.
In Acts 13:48 we see many "ordained" Gentiles glorifying God. They were under the mercy of God's prevenient grace waiting for the Word of Truth.
In Acts 16 Paul finds a young man already awakened, taught by his mother and grandmother, ready to be led in the way of faith. Then he found Lydia leading a group of awakened women in a riverside prayer meeting, ready to receive the things Paul preached. Next the Philippian jailer had knowledge of God enough to ask, "Sirs, what must I do to be saved?"
Also in Acts 17:4 at Thessalonica we find devout Greeks, and chief women who were under prevenient grace waiting to be told of the gift of saving grace. At Berea the Bible searchers were hungry to hear God's Word. At Athens men were ignorantly worshipping the unknown god and certain men clove unto Paul and believed on Jesus.
At Ephesus in Acts 19 the grace of God preceded Paul's preaching of Christ, but they were not New Testament Christians until Paul came and sensed their lack of the Spirit (which was a lower experience than the New Testament afforded) and exhorted them to be baptized in the name of Jesus and receive the Holy Spirit, thus bringing them up to the New Testament standard.
Many today have felt this work of the Spirit and were well on their way to a new birth experience when they have been told to claim an experience. In reality they are merely awakened sinners and full of guilt and fears and many fall away and give up the profession as a lost cause. There must be multitudes in evangelical churches that have been awakened by this glorious prevenient grace and claim to be born again and are encouraged to testify to it and told to "reckon" they are saved and not to expect any conscious indwelling of the Holy Spirit. They are told they have the Holy Spirit whether or not they are aware of it. If in a holiness church, they are instructed to on into holiness and receive the Holy Ghost as a second blessing. That they need the Holy Ghost is for sure, but when and if they do, they are encouraged to testify to Christian perfection, when in reality they have truly been born again and made a new creature in Christ.