J.I. Packer explores this topic with cross-cultural evangelism in mind.  Here’s a summary.

1. Three preliminary thoughts

(a) The communication of the gospel must be determined by its content

The content includes a diagnosis of the human condition, value-judgments on the life that is, and the life that might be, lived, and a call to respond in radical commitment.  Now this content must be verbalised, and it must be preached (i.e. explained and applied).  Such media as instrumental music, pictures, sculpture, or dance may reinforce the message, but only preaching can communicate it.  Nor can the theologian take the place of the ambassador.  Heb 1:1-3 describes God’s Son as a preacher even before he is described as as priest, sacrifice and mediator.  This is borne out by the Gospels themselves, which present him first of all as preacher of the Gospel of the kingdom (Mk 1:14f; Mt 4:17, 23; Lk 4:16-21; Jn 3:3-15).  So, preaching must continue as a main activity of the church, and the manner of the preacher must back up his matter.

(b) Problems in communicating the Gospel raise questions about its content

If we cannot convince others of the truth and relevance of the message them we  must ask ourselves if we have understood it aright ourselves.  Bultmann, for example, saw the miracle-stories as obstacles to belief, and so proposed a programme of demythologization.  Similarly, J.A.T. Robinson posited ‘the end of theism’ because he thought that the idea of a transcendent God could not make sense to modern western man.  But in both cases the baby has gone out with the bath-water.

It is never safe for the Christian communicator to conclude that that the less you commit yourself to assert, the easier it will be to assert it, or to treat objections to a particular tenet as a sign that it is dispensable.

The truth is that God has made known in Christ certain absolutes – such as his sovereign providence and his particular grace – and we must at all costs maintain these givens when seeking to communicate the Gospel, even across cultures.

(c) Our own assumptions about the content of the Gospel can become obstacles in communicating it

Whereas God’s revelation of himself in Christ was culturally particularised, all subsequent understandings of the Gospel are culturally conditioned.  Any culture not only clarifies some things but also obscures others.  And we shall see the specks produced by other peoples’ cultures much more clearly than the motes produced by our own.  We shall be tempted to ascribe a finality and universality to those expressions (theological, liturgical and behavioural) of the Gospel that we know best, whereas it is only the Gospel itself that has finality and universality.

Exporting the Gospel in one or other of its cultural expressions will not only transmit idiosyncracies, but tend to ignore matters of importance.  For example, Western evangelicalism is very weak on the doctrine of creation.  This has led us to (a) weaken our witness to the uniformitarian myth; (b) trivialise our discussion of the relationship between the witness of Scripture and that of natural science; (c) ignore the cosmic dimensions of redemption; (d) deny the corporate aspects of our faith; and (e)  an attenuated theology of nature and the natural.

Now should anyone take over any version of the Western evangelical tradition in theology as a final standard, he would be buying along with many strengths this chronic and often overlooked weakness on creation.  It is important that such parchases should be outlawed, lest in retrospect someone should feel himself to have fallen victim to a confidence trick.

So, we must learn to distinguish between the unchanging content of the Gospel and the changing cultural forms in which it is expressed.  These cultural forms are the product both of fallen human nature and of divine comment grace, so cultures may learn from, as well as critique, one another.

2. What, then, of the content of the Gospel?

The underlying word, euaggelion, good news, is used 60 times in Paul’s writings.  It refers to God’s work in Christ for the salvation of the world.  Specifically, it incorporates the message of Christ’s incarnation, death, resurrection, reign and return.  Six overlapping stories are involved:-

Story #1.  God’s purpose: the kingdom

All of humankind is subjected to sin and death, and all of creation to futility and corruption.  But God’s eternal plan has been to restore this situation through the God-man Jesus Christ.  God will exert his kingship by bringing in his kingdom.  In his kingdom, trusting and obeying Christ, his vice-regent, is God’s appointed way of returning us from sin to God’s service.  God’s kingship over Israel was a preparation for this kingdom.  When at the appointed time Christ came, God’s prepared people rejected him, but this very rejection meant world-wide redemption.  In this story, the goal is a restored and perfected cosmos, and the Gospel call is to abandon rebellion, acknowledge Christ as Lord, accept forgiveness, enlist on the victory side, be faithful and life in hope of God’s final triumph.

Story #2 – God’s people: the church

In this fallen world people are alienated from God and from one another.  God has acted to created a new people who will live for him and for one another in covenant love and loyalty.  God established a covenant with Abraham and his descendants.  He gave the law, which showed what behaviour pleased him, and a cultus, with sacrifice at its heart, whereby sin might be dealt with.  A pattern of judgement and renewal was set up.  When Christ came to set up a new form of the covenant by his self-sacrifice, Israel spurned him, and he became in himself the faithful remnant.  In him Israel was reconstituted as comprising believing Jews and Gentiles alike, and the church will thus remain one city, one family, one flock for ever.

The pattern of judgement and renewal is fulfilled in Christ’s death and resurrection, which themselves give shape to the Christian life, as baptism shows.

Outwardly, God’s covenant people are humiliated, dispersed, opposed and distressed.  But inwardly their life is one of union and communion with the risen Christ, as the Lord’s Supper proclaims.  The Church is one body, each member serving the whole, animated by the Holy Spirit.

In this story, the goal is for God to have a people who are bound to him in love, and whose unity-in-diversity demonstrates to a watching world God’s many-stranded wisdom (Eph 3:10).  The Gospel call is to accept a share in this life and a place in God’s family by bowing to the One who loved the church and gave himself for it.

We turn now, in outlining the content of the gospel, from two stories about God to two stories about Jesus Christ.

Story #3 – The grace of Christ

The grace of God in Christ more than matches our great need; his love far outweighs our unloveliness.  Jesus is set forth as prophet (teacher and guide), priest (mediator and intercessor) and king (master and protector).  The focal point of his saving work is the cross, which demonstrates his love and accomplishes our redemption, propitiates God’s wrath, provides a substitutionary sin-bearing, effects our justification and adoption, and transforms us by the new birth and the progressive sanctification of the Holy Spirit.  The gospel calls us to all this (and more) by an invitation to faith.

Story #4 – The glory of Christ

The Father has loved the Son from all eternity, and delights for him to be glorified, Jn 5:20-22.  The Son loves the Father and delights to do his will.  As the Father has made the Son pre-eminent in creation and providence, so now he makes him pre-eminent in the economy of redemption.  He has not only reward the Son’s self-humbling by restoring to him his original glory, but has made him head of the church and Lord of all.  In this story, God’s goal is the praise and glory of Jesus Christ, and the Gospel call is a summons to join those who will spend all eternity honouring his name.

Story #5 – God’s image restored

Turning now from stories about God and about Christ that expound the content of the gospel, there are two that are about man.  Humans have been made to display God’s image by reflecting God’s goodness and creativity.  We have all fallen short of this vocation, but God is now restoring it in his disciples.  See Col 3:10.  In this story, God’s goal is to see his character reflected in us, and the Gospel call is to let ourselves be renewed so that we become fully human.

Story #6 – Humanity’s joy begun

Without Christ we are in a pitiable state – guilty, lost, and without hope.  But Jesus Christ gives peace, meaningfulness, purpose, and an assurance of final glory in the Saviour’s presence.  In this story, God’s purposes good for us, and the Gospel call is a summons to enter into the joy that Christ gives.

Each of the six stories is authentic gospel, although the full message only appears when they are put together.

But the stories are not merely ‘models’ of human devising, but are God-given anthropomorphisms intended to be normative for our understanding.  Of course, they do not give us exhaustive truth, but are true and trustworthy so far as they go.  Nor can we cut them loose from their original cultural contexts and transpose them to our won without at least explaining that such transposition merely illustrates the original meaning and does not, strictly speaking, translate it at all.

3. The Gospel’s content today

So, what is the content of the Gospel for today in any of the cultural settings which we find around the world?

(a) God

The Gospel tells of God who is our maker and to whom we are accountable.

(b) Sin

The Gospel tells of sin, understood as failure to meet our maker’s claims on us, and as rebellion against his authority, transgression of his law, missing the mark he has given us to aim at, and as guilty an dunclean before him.

(c) Christ

The Gospel tells of Christ, his life, death, resurrection and reign.    People need to know who he is, and what he has achieved in bearing away our sin.

(d) Faith, repentance, and discipleship

Believing the Gospel message, we cast ourselves on Christ. as our only hope.  In repentance we experience a change of heart and mind, and determine to lead a new life of service to our Saviour and king.  As disciples, we becomes both learners and followers of Christ.

(e) Newness

The Gospel tells of newness.  The Holy Spirit both assures and enables.  He impels fellowship and ministry in the church and service and outreach in the world.  And there is a new hope: for Christ’s reign, now invisible, will one day become public and visible, and he will usher in new heavens and a new earth.

4. The communication of the Gospel

In conclusion, a few thoughts about the communication of the Gospel.

(a) Character more than technique

The key to persuasive communication of the Gospel lies more in character than in technique.  Paul was not eloquent by the standards of the day, 2 Cor 10:10, but he knew his own mind and understood others as well.  Although he relied on the Holy Spirit, he did not despise the ordinary means of persuasion.  He made every effort to avoid cultural barriers to communication, 1 Cor 9:19-22.  He gave of himself unstintingly, and allowed himself to be stripped of cultural pretension, Phil 3.

(b) Follow the guidelines God has given us

We should follow the God-given procedural guidelines for communicating the Gospel.  We follow the lines of the biblical story, we keep close to the text of Scripture, and above all we focus on the person of Christ.  We do not shrink from declaring the whole counsel of God, but we distinguish between milk and meat, between foundation and superstructure.  We show how the Gospel shapes our relationships at home and in the family and elsewhere.  We show respect for other cultures as well as our own, however pagan they may be.

(c) It is not easy

Christian communication is not easy.  There is not necessarily anything wrong with what we are doing if we meet anger and opposition: for this was often the experience of our Lord too.  The parable of the sower shows this, as does the reaction of Chorazin and Bethsaida, Mt 11:1-6.

Based on J.I. Packer, ‘The Gospel – Its Content and Communication’, in Selected Shorter Writings 2.