Law, Prophets, and Christian Duty
A sermon for 8 February 2026
Isaiah 58:1-12
1 Cor 2:1-12
Matthew 5:13-20
Isaiah 58 (our first reading this morning) is one of the most bracing, inspiring and sobering passages in the Hebrew Scriptures. The prophet addresses a people who are religiously serious, theologically articulate, and outwardly devout. They fast, they pray, they seek God “day after day.” And yet God’s verdict on their worship is devastating: it is not enough.
It’s deficient because their religious observance has become detached from the suffering of their neighbours. They fast but ignore exploitation; their prayer coexists with oppression, and their worship leaves unjust structures intact. Their spirituality is hollow; all feathers and no bones.
The heart of the passage is unmistakable. True worship is inseparable from justice. The fast that God chooses is not ritual deprivation but moral action: loosening the bonds of injustice, undoing the thongs of the yoke, letting the oppressed go free, sharing bread with the hungry, and housing the homeless poor. In Isaiah 58, intervention on behalf of the exploited is not optional spirituality; it is covenantal obligation – a requirement of being a person of God.
This moral principle is not unique to Isaiah. It runs like a strong current through the prophetic tradition. Amos thunders against those who “sell the righteous for silver, and the needy for a pair of sandals” (Amos 2:6) and famously declares that God despises worship that is unaccompanied by justice – and lots of it: “Let justice roll down like waters, and righteousness like an ever-flowing stream” (Amos 5:24). Micah (as we heard last Sunday) distils Israel’s vocation into a single sentence: “to do justice, and to love kindness, and to walk humbly with your God” (Micah 6:8). Jeremiah condemns kings who build palaces through unrighteousness and exploitation (Jeremiah 22:13–16). Zechariah insists that true religion consists in showing kindness and mercy, refusing to oppress the widow, orphan, foreigner, or poor (Zechariah 7:9–10). Across the prophets, the message is consistent: fidelity to God is measured by the defence of the vulnerable.
It is against this background that Jesus’ words in today’s Gospel passage (Matthew 5:13-20) must be heard, particularly the part where he says, “Do not think that I have come to abolish the law or the prophets, I have come not to abolish but to fulfil.” He then adds the striking claim that not one letter of the law will pass away until all is accomplished. At face value, this sounds like an endorsement of the entirety of the Torah, all 613 commandments, moral, ceremonial, and dietary alike.
This has generated a long-standing interpretive tension within Christianity. One possibility is that Jesus intends his followers to observe the full legal code of the Hebrew Scriptures. Another is that Jesus affirms the enduring moral vision of the law and the prophets—especially their demand for justice—while freeing his followers from ritual and ethnic boundary-marking regulations.
The Church, from a very early stage, adopted the latter view. Dietary laws, circumcision, purity codes, and sabbath regulations were not imposed on Gentile believers. What endured was the ethical core of the tradition, sharpened and intensified by Jesus’ teaching. Yet it is important to acknowledge that this was not the only interpretation available, nor perhaps the one Jesus himself most immediately intended.
A number of contemporary scholars have argued that Jesus should be understood as a Torah-observant Jewish teacher whose message was directed primarily to fellow Jews. Amy-Jill Levine repeatedly stresses that Jesus speaks within Judaism, not against it. In her work on the Sermon on the Mount, she argues that “fulfilment” does not mean replacement or cancellation but faithful embodiment. Jesus intensifies the law rather than relaxing it. Commands against murder extend to anger; prohibitions on adultery reach into desire. In this reading, Matthew 5 reinforces Torah observance while pressing it to its deepest ethical intent.
Bart Ehrman, though writing from a different theological perspective, reaches a similar historical conclusion. He argues that the historical Jesus likely expected his followers to continue keeping the Jewish law in anticipation of God’s imminent kingdom. The relaxation of Torah observance, Ehrman suggests, is a development that occurs later, especially as the Jesus movement becomes predominantly Gentile.
James Tabor goes further still, portraying Jesus as a thoroughly Jewish messianic figure whose earliest followers—including groups such as the Jerusalem church under James—continued to observe the law. For Tabor, Matthew’s Gospel preserves traces of this original Torah-faithful movement, even as later Christianity moved in a different direction.
Taken together, these scholars remind us that the Church’s settled position did not emerge without debate, struggle, and theological development.
Be that as it may, by the second century a consensus had emerged. Christians did not understand themselves to be bound by the full Mosaic law. They did, however, understand themselves to be bound—unavoidably and permanently—by the prophetic demand to resist injustice. Jesus was seen not as relaxing that obligation, but as radicalising it. Love of neighbour, care for the poor, and solidarity with the oppressed became non-negotiable marks of Christian faithfulness.
Christian history bears witness to individuals who took this conviction seriously, often at great personal cost. William Wilberforce devoted decades of his life to the abolition of the British slave trade, motivated explicitly by Christian conviction and sustained by a community of evangelical reformers. His struggle was slow, politically costly, and emotionally exhausting, yet it helped dismantle one of the great injustices of the modern world.
In the twentieth century, Martin Luther King Jr. drew deeply from the prophetic tradition and the teachings of Jesus. His vision of racial justice was explicitly theological. Amos, Isaiah, and the Sermon on the Mount shaped his imagination as much as any political theory. King’s nonviolent resistance to segregation was an enactment of Isaiah 58 in a modern key: loosening unjust bonds and letting the oppressed go free.
Other examples could be multiplied: Archbishop Desmond Tutu’s opposition to apartheid; Óscar Romero’s defence of the poor in El Salvador, which ultimately cost him his life. And, of course, on Waitangi Weekend we shouldn’t forget those who have fought against the worst excesses of colonialism in this land – people like Te Whiti o Rongomai III of Parihaka, and Dame Whina Cooper.
Again and again, Christian resistance to oppression has arisen where Scripture is read not as a refuge from the world’s pain, but as a summons into it.
What, then, might this mean for Christians today? Most of us will not lead mass movements or confront empires. But the prophetic imperative is no less real for being ordinary. It begins with attention: learning to see who is being exploited and why. It continues with solidarity: refusing to benefit uncritically from systems that degrade others. It may involve practical acts of hospitality, ethical consumption, political engagement, or public witness.
Isaiah 58 promises that when God’s people live this way, light breaks forth like the dawn. The promise is not of moral heroism, but of healing—of communities repaired and lives restored. Jesus did not abolish that vision. He fulfilled it by placing it at the centre of life with God.
The question for the Church is not whether the prophetic call still stands. It does. The question is whether we are willing, in our own time and place, to live as though it matters.
Tony Surman