We are all aware of the rising consumer approach to church. We have even begun to use the phrase 'church shopping' when talking about finding a new church, and often make our decision based on whether the worship was good, if we liked the preacher, or even who has the best coffee!

As consumerism increased with the rise of disposable income after the Second World War, and church attendance fell as a result of the increasingly secularist influence in society, many churches felt they had to adapt or else be left behind. Unfortunately, this adaptation has not been exclusively left to the different tastes in coffee or music. In an age where we are offended easily, the gospel message has been tailored to the particular demands of the acceptance-based, tolerance-promoting culture. Grace included.

First up, we have Paul's free grace - 'for all have sinned and fallen short of the glory of God, and all are justified freely by his grace through the redemption that came by Christ Jesus.' We like a good bargain and the idea of God's grace at no price is a pretty good deal.

But we like to have our options, don't we? Bonhoeffer's The Cost of Discipleship is a Christian classic, with his phrase 'costly grace' being well known, perhaps primarily due to Bonhoeffer's own costly witness. With this offer, however, grace is not the free gift we see advertised by Paul, but a more costly endeavour.

For the consumer church, Bonhoeffer's writing on the cost of grace is unappetising when the free grace of Romans 3 is on offer. Indeed, because of this many churches feed into the consumer mentality by promoting the free gift that all can receive, almost like when you sign up for a new gym membership and get a free water bottle in return.

The trouble with this is that the gift of grace has been read with the modern context in mind. Any good interpreter of Scripture knows that in order to understand what implications the Bible has today, the original context must first be considered. Whilst today we understand a gift as being free in the sense of pure altruism, that is, without the expectation or demand of a response, this is not what was understood in the first century.

John Barclay in his incredible work Paul and the Gift, shows how the first century Greek society practised gift giving. Whilst a gift could be a result of profound generosity by the giver, the recipient was aware that if they accepted the gift, it was 'crucial to give a well-measure return.' Paul would have been well aware of the implication of gift giving in his society.

Nevertheless, the shock factor of God's gift of grace is that, unlike Greek society where gifts would have been given only if the giver was sure their gift would be equally reciprocated, God gives without regard as to whether or not we will reciprocate, fully aware that we cannot give an equal return. The gift of grace comes through the life, death and resurrection of Jesus Christ, God's only Son. What do we have that would even come close to an equal return for this? Paul talks of free gift when he considers the giver, who gives with no prior regard for our ability to respond.

This does not mean that we are exempt from reciprocation, however. Though God gives without calculating whether or not we can respond equally, if we accept the gift we are entering into a relationship with God where we must respond in return. This is where Bonhoeffer's 'costly grace' is put into practise. Jesus talks of the cost of discipleship in Luke 14, instructing his disciples to bear their own crosses (v.27) and to count the cost (v.28). The only response close to what God has given us through His Son, is to give our own lives in return. That's the cost of the gift of grace.

As we look back at the grace menu which offered us free or costly grace, we do not see Paul claiming that grace is free so that we can have everything in return for nothing. Neither is Bonhoeffer advertising that we can only receive grace through the works that we do. No, they both make clear the incongruity of the grace of God, and the expectation that is placed upon us if we accept this gift.

Today, Christians (particularly those of us in the West) are in danger of missing this nuance in Paul's writing which would have been fundamental to the meaning of his argument. Bonhoeffer highlights this integral call not only to accept but to obey the call to discipleship that grace demands, and that is often neglected in our consumer society which takes for granted that gifts demand nothing in return. The cost of this simple grace is high, or else it ceases to be grace at all.

Elizabeth Davey is a Christian writer and blogger.  Read more from her at Faith in Action.