Telling people the need for the gospel, both their felt need and the real need, is plainly important, but it is not itself the gospel. When we have explained what God has done for us in Christ - the gospel - then we may go on to explain the benefits of receiving the gospel and the perils of ignoring it. However, telling people that they can choose either heaven or hell is not telling them the gospel. Telling them, as Peter did, that repentance and faith go hand in hand with the gift of the Holy Spirit is important, but it is not the gospel.
Whenever people's sense of assurance of salvation is expressed in the first person, something is amiss. When the question "How do you know God will accept you?" is answered by "I have Jesus in my heart, " "I asked Jesus into my life, " "The Holy Spirit is in me, " and so on, the real gospel basis for assurance needs to be reviewed. We rejoice when the answer comes in the third person: "God gave his only Son to die on the cross for me, " "Jesus died, rose, and is in heaven for me." When the focus is on the finished and perfect work of Christ, rather than on the yet unfinished work of the Spirit in me, the grounds for assurance are in place.
- Graeme Goldsworthy, Preaching the Whole Bible As Christian Scripture: The Application of Biblical Theology to Expository Preaching, 95