The Gospel proclaimed by Jesus’ first followers was this: that God had appointed the man Jesus as the one through whom God would judge the surrounding nations;
and had demonstrated this to be so, in the face of this Jesus having been rejected by the leaders of his own people, by raising him from death-by-Roman-execution
—Rome embodying the surrounding, oppressing, nations at that moment in history.
To proclaim “Jesus is Lord!” was a direct, political refutation of the claim of the Roman Empire that Caesar is Lord—a claim demonstrated by the Pax Romana, the peace that the whole world enjoyed under Caesar’s benevolence, a peace Rome was prepared to crush all revolt to uphold.
Given the impossibility of effecting change by might or power (Rome would crush the Jewish nation in AD70, making it clear in the process that God was playing a longer game than anticipated)
the inevitability that, through Jesus, God would judge Rome (and, however complex a judgement, this would be fulfilled through the conversion of the Roman Empire, the bowing of Caesar before Jesus’ throne)
the consistent advice of the authors of the letters of the New Testament was, don’t rise up against authority: they are only there by God’s appointing.
It is a stretch too far to extrapolate from this that every world leader, tyrant or hero, whether dictator or with democratic mandate, is in power as a manifestation of the will of God. Or, indeed, that the fall of every world leader, by General Election or bloody coup, is also the will of God. Here lies madness.
The point was that Rome had not yet been judged, because God had not yet enacted the judgement. This was, initially, thought to be immanent; both the timing and nature of that judgement being reinterpreted after the fall of Jerusalem.
Rulers are judged, throughout scripture, according to their posture before God, and the impact of their governance on the welfare—physical and spiritual, for scripture knows no division—of the peoples.
World leaders are not brought to power by God; nor are they the anti-Christ, except in as much as they position themselves as a Great White (often) Saviour, or Caesar.
Boris Johnson is not God’s man for this moment, and neither is Donald Trump or Vladimir Putin. He is just a man. As people of faith, we are free to evaluate him, to affirm here and oppose or resist there.
As for Jesus, his own role has also changed. The judgement of the nations surrounding and oppressing the ancient Jewish nation is long-since complete. This is not the primary Gospel for our times. That may, in fact, be better expressed in terms of judgement on humanity for oppressing the wider creation, for crushing our shared home. But that is content for another post.