The Holy Spirit is resisted by those who are lost. They thereby have "insulted the Spirit of grace" (Hebrews 10:29). The Bible teaches that people resist the Holy Spirit, because their hearts have not been changed by the grace of God. The responsibility of man is his own just condemnation in rejecting the gospel of Christ.
"You stiff-necked and uncircumcised in heart and ears! You always resist the Holy Spirit; as your fathers did, so do you" (Acts 7:51). Only the Spirit of God can change the heart of man, which means our mind, will, and emotions. By resisting the Holy Spirit, people are insulting the only one who can apply the gospel of Christ to our hearts.
The Holy Spirit, who changes the corrupt heart of man, is the same Spirit who convicts the heart of man. Conviction is grace that precedes new birth (John 16:7-11). When conviction is resisted, grace is resisted. Conviction deals specifically with the sin of unbelief, in essence, rejecting the gospel of Jesus Christ.
Why would anyone reject the gospel of Christ? Jesus said, "And this is condemnation, that the light has come into the world, and men loved darkness rather than light, because their deeds were evil" (John 3:19). Therefore, the one who is resisting the Holy Spirit has no one else to blame for his own just condemnation.