“There is, then, an evangelical way to preach the Gospel and an unevangelical way to preach it.
The Gospel is preached in an unevangelical way, as happens so often in modern evangelism, when the preacher announces:
This is what Jesus Christ has done for you, but you will not be saved unless you make a personal decision for Christ as your Savior.
Jesus Christ loved you and gave his life for you on the Cross, but you will be saved only if you give your heart to him.
In that event, what is actually coming across to people is not a Gospel of unconditional grace but some other Gospel of conditional grace which belies the essential nature and content of the Gospel as it is in Jesus. It was that subtle legalist twist to the Gospel which worried St Paul so much in his Epistle to the Galatians.
To preach the Gospel in that conditional or legalist way has the effect of telling poor sinners that in the last resort the responsibility for their salvation is taken off the shoulders of the Lamb of God and placed upon them.
How, then, is the Gospel to be preached in a genuinely evangelical way?
Surely in such a way that full and central place is given to the vicarious humanity of Jesus as the all-sufficient human response to the saving love of God which he has freely and unconditionally provided for us.
We preach and teach the Gospel evangelically, then, in such a way as this:
God loves you so utterly and completely that he has given himself for you in Jesus Christ his beloved Son, and has thereby pledged his very Being as God for your salvation. In Jesus Christ God has actualised his unconditional love for you in your human nature in such a once for all way, that he cannot go back upon it without undoing the Incarnation and the Cross and thereby denying himself.
Jesus Christ died for you precisely because you are sinful and utterly unworthy of him, and has thereby already made you his own before and apart from your ever believing in him. He has bound you to himself by his love in a way that he will never let you go, for even if you refuse him and damn yourself in hell his love will never cease. Therefore, repent and believe in Jesus Christ as your Lord and Saviour.”
Thomas F. Torrance, The Mediation of Christ
Our theology of the gospel is essential to our understanding of evangelism and mission.