A while ago an atheist friend who also works with homeless people said to me, "My motives are purer than yours. I do this work simply to help people; you do it so you can get into heaven."
We endure in this work because we are inspired by our hope that God will one day bring complete renewal to this broken world, Kuhrt observes.
I did my best to explain that while I am motivated by my faith, I have never seen this work in terms of earning "brownie points" for the afterlife.
But it prompts the question: Why is it that so many homeless charities were started by committed Christians?
Why is it that churches run the vast majority of food banks? Why is it that more than 280 churches in London alone will open as night shelters for homeless people this winter?
Of course, Christians don't have any monopoly on making a difference to those in need, but even the most hard-bitten critics of Christianity have to admit that the church makes a massive contribution in combating poverty.
After all, what other voluntary institution can rival the scale and scope of what the church is doing?
But why is this the case? Is it because Christians want to gain a place beyond the pearly gates? In more than 20 years of being involved in this kind of work, I have never heard anyone claim this as a motivation.
So is it because Christians are nicer people? Again, experience doesn't tell me this is true.
Churches have just as many cranky, argumentative and grumpy people as you find anywhere else.
I think the answer to this question is found in a verse from Paul's first letter to the early church in Thessalonica: "We remember before our God and Father your work produced by faith, your labor prompted by love, and your endurance inspired by hope in our Lord Jesus Christ." (1 Thessalonians 1:3)
Paul praises the Thessalonian Christians for their work, labor and endurance. But this triplet of actions is rooted in their belief about what God had done for them through Jesus.
Their outward actions are motivated by an inner experience of faith, love and hope. It is work produced by faith, labor prompted by love, and endurance inspired by hope.
The Bible makes abundantly clear that action is at the heart of a faithful Christian life – faith without deeds is dead (see James 2:14-26).
But our actions are not rooted simply in confidence about our intrinsic qualities, our generosity, kindness or stamina.
The Bible contains no dewy-eyed optimism about the goodness of human nature. Rather, Christian activism is rooted in what God has done.
Our work is produced by the faith we have been given. Our labor is prompted by the love and acceptance we have experienced.
We endure in this work because we are inspired by our hope that God will one day bring complete renewal to this broken world.
This is the basis of the strongest theology for social action.
God's grace, acceptance and love have to remain central: It is the rock on which we must base all our faltering efforts. All other ground is sinking sand.
And I think this is the key reason for the enduring efforts of churches and Christians, both in the United Kingdom and globally, to combat poverty and live lives of generosity and love.
Of course we mess up, get things wrong, and are weak and inconsistent. But we point to one who isn't. We are not the ones who can save people, but we believe in one who can.
The key factor is that the church draws on resources beyond itself. At its best, the church lives out actions rooted in faith.
We seek to love because we have been loved. We endure because we are inspired by the hope we have in Christ.
Jon Kuhrt is the executive director of social work at West London Mission and is a member of Streatham Baptist Church in South London. A version of this column first appeared on his blog, Resistance and Renewal, and is used with permission. You can follow him on Twitter @jonkuhrt.