Herbert McCabe was, by widespread acclaim, one of the greatest Catholic thinkers in the English speaking world during the final quarter of the last century. He was also deeply committed to radical left‐wing politics. What is the relationship between these two facts? I lay out what I take to be the key themes in McCabe's politics before arguing that, in contrast to significant strands in present day political theology, he had a keen sense of the respective roles of faith and reason in guiding political action. This allowed him to commit himself to a politics which was more radical than much of what has followed him, whilst having a clear sense of how Christian faith ought to be allowed to condition political engagement. The article concludes by drawing out lessons from McCabe for thinking about faith and politics. Not least of these is that we ought to avoid the lure, often articulated in terms of the ‘unifying’ role of the Church, to eschew conflict.