Have you ever shared the gospel with someone and experienced it being devoid of power and impact? Perhaps your thought was, "If I had just been a better speaker then they would have believed!" Or your thought may have been, "If I only had more knowledge of the Bible then I could've answered all of their questions and they would have received the Lord Jesus!"
Although these thoughts may have some truth to them, what was truly lacking was probably the convicting work of the Spirit. To convict is to impress with a sense of guilt, which is purely an inward matter. As the Spirit operates on a person, convicting them of their sinfulness or wickedness, that person becomes open to hearing the good news of Jesus Christ. When the gospel is shared with them, it corresponds with the inner sense of guilt they've been feeling and thus the gospel takes root and has impact.
Our prayer for our friends or family to be saved should not be for us to be more eloquent or have more Scriptural knowledge, we should pray for the Spirit to convict them of their sin.
Although these thoughts may have some truth to them, what was truly lacking was probably the convicting work of the Spirit. To convict is to impress with a sense of guilt, which is purely an inward matter. As the Spirit operates on a person, convicting them of their sinfulness or wickedness, that person becomes open to hearing the good news of Jesus Christ. When the gospel is shared with them, it corresponds with the inner sense of guilt they've been feeling and thus the gospel takes root and has impact.
Our prayer for our friends or family to be saved should not be for us to be more eloquent or have more Scriptural knowledge, we should pray for the Spirit to convict them of their sin.
The portion below from The Conclusion of the New Testament was of great help to me. I hope you'll find it helpful too.
And when [the Spirit] comes, He will convict the world concerning sin and concerning righteousness and concerning judgment: Concerning sin, because they do not believe into Me; and concerning righteousness, because I am going to the Father and you no longer behold Me; and concerning judgment, because the ruler of this world has been judged.
–John 16:8-11
John 16:8-11 reveals that the Spirit works to convict the world—mankind—concerning sin, righteousness, and judgment. In verse 8 the Lord says of the Spirit, "When He comes, He will convict the world concerning sin and concerning righteousness and concerning judgment." Here to convict means to convince, to condemn, to cause people to rebuke themselves. The Spirit always convicts the world concerning the three matters of sin, righteousness, and judgement. Sin entered through Adam (Rom. 5:12), righteousness is the resurrected Christ (1 Cor. 1:30), and judgment is for Satan, who is the author and source of sin (John 8:44). We were born of sin in Adam. The only way to be freed from sin is to believe in Christ, the Son of God. If we believe in Him, He will be righteousness to us, and we shall be justified in Him (Rom. 3:24; 4:25). If we do not repent of the sin in Adam and believe in Christ the Son of God, we shall remain in sin and share the judgment of Satan for eternity (Matt 25:41).
In John 16:8-11 the convicting work of the Spirit is related to three persons: Adam, Christ, and Satan. We all became fallen in Adam, but we may believe in Christ and be justified. Because Christ was accepted by God in His death, God raised Him up from the dead, and now He becomes righteousness to all who believe in Him. Satan, the source of death, has been judged and destroyed through Christ's death (Heb. 2:14). The three main items are related to these three persons: sin is related to Adam, righteousness is related to Christ, and judgment is related to Satan. We were born of Adam, but we have believed in Christ and have received Him as our righteousness. However, all those who do not believe in Christ will suffer the judgment of Satan. Because they remain followers of Satan, they will have the same destiny as Satan.
In John 16:9 the Lord says that the Spirit would convict the world "concerning sin, because they do not believe into Me." Here we see that for a person to perish the unique sin is to not believe in the Son (3:16). The sin here is the unwillingness to be transferred from Adam into Christ. If people wish to remain in Adam, it means that they want to remain in the old realm and not move into the new realm, which is Christ. There is no need for us to commit sin in order to perish. I we simply do not believe in the Lord Jesus, we are already qualified to perish. We may be a gentleman, but as long as we do not believe in the Lord Jesus, we are destined to perish. The unique way to escape from our sinful situation is to believe in the Lord; the unique sin that qualifies us to perish is to not believe in Him. Therefore, the key today is whether we believe or not. If we believe, we shall be transferred out of Adam into Christ. But if we do not believe, we shall perish.
–Witness Lee, Conclusion of the New Testament pp. 2944-2945 from HWMR