This message is aimed at showing that the New Testament Gospel is totally non-negotiable. You can only be saved by a personal relationship with Jesus Christ who has lived and died to save His people. The Holy Spirit testifies to the fact that Jesus alone is able to save.
10 Whoever believes in the Son of God has the testimony in himself. Whoever does not believe God has made him a liar, because he has not believed in the testimony that God has borne concerning his Son. 11 And this is the testimony, that God gave us eternal life, and this life is in his Son. 12 Whoever has the Son has life; whoever does not have the Son of God does not have life.
1 John 5:10-12 English Standard Version (ESV)