Charles Spurgeon wrote, "I never knew one who could put his hand on his heart, and say, 'I believed in Jesus without the assistance of the Holy Spirit." Spurgeon understood clearly that the Holy Spirit applies the salvation of the Lord Jesus Christ in our lives. According to the Bible, faith is an abiding gift of the Holy Spirit (1 Corinthians 13:13). Without the Holy Spirit, your salvation could not be applied.
Without the Holy Spirit, we would not see the need for Christ. His work is to convict us of the sin of unbelief, that is not believing in the Lord Jesus Christ (John 16:7-11). He convinces us concerning the truth of the gospel (1 Corinthians 15:1-4). The Holy Spirit is the Spirit of truth, guiding us into all truth. Christ is the truth (John 14:6). The Holy Spirit leads us to know and understand the truth of Christ.
Without the Holy Spirit, your heart could never be changed to have a personal relationship with God through Christ our Lord. The heart is your inward person. That is your mind, will, and emotions. Christ lives in your heart through the Holy Spirit (Romans 8:9).
Without the assistance of the Holy Spirit, we could not truly understand the gospel. Without the assistance of the Holy Spirit, we would not be willing to believe the gospel. Without the assistance of the Holy Spirit, we would have no remorse nor sorrow for sin. By the Holy Spirit, your salvation is applied.