Imagine you're in a conversation with someone of another religion. At some point you might ask them: "Are you sure of heaven/Valhalla/getting beamed to the mother ship?" (delete as appropriate).
This is a good question because no other god actually saves. They might talk a big game but they can't be counted on to do the business. And so the follower of this other religion will be forced back on themselves. They'll either openly confess 'No' or they'll be full of bravado and demonstrable good works but the most they can say is, "I hope so." And when they confess their lack of assurance it's enough to bring you to tears. What wicked demon has ensnared you that you may even kill yourself in its service yet have no hope of its favour!?
Well don't we see the same thing with the carbon-cutting gospel? I receive emails from an old university friend (I'll bet many of you get the same ones - his global advocacy group has become massive). But for all the candlelit vigils, the millions strong petitions, the vast sums raised and ambitious goals - the lack of assurance is palpable. Every email ends "with hope." But you just wonder don't you.
It seems to me that even the most committed activist working to tax carbon into oblivion doesn't really think their gospel will deliver. The most optimistic talk of the climate campaigner sounds so much like the devout Mormon who 'hopes' they'll make it. Maybe I'm reading things in here, but I get the distinct impression that deep down their whole fear-driven carbon-cutting works both hide the fact and spring from the fact that they don't think it's going to happen. Not deep down.
Oh they hope so! And they hope it enough to wear themselves out in anxious labour. But there's no assurance.
So how do we preach to the climate campaigner? Let me suggest not by agreeing with their apocalyptic, pseudo-messianic gospel and then adding in a few Jesus extras to get the job done. (You're correct in your assessment of the planet's destiny and true rulers, but let me add in Jesus who helps us to be the saviours!)
No, that's not the way. But not because we have no compassion. We do. It is desperate to see them so harassed and helpless like sheep without a Shepherd. And so the way forwards is to teach them (Mark 6:34). And perhaps especially we might paint for them a cosmic picture of the new heavens and the new earth, the home of righteousness. Not just a reduction in the number of hurricanes, but a crystal sea like glass! Not just preventing the displacement of people groups but their planting in the land! Not just the protection of the trees but their joyful worship! Not the maintenance of adequate food supplies but the richest of meats and wine dripping from the hills! Not alleviation of drought but the Lamb shepherding us to streams of Living Water! Not simply the preservation of lions and lambs but their reconciliation! And a little Child will lead them. We introduce them to this Child and He will calm all fears. Because He is able to deliver on this future. He guarantees it.
Maybe we need to be saying to our climate believer friends "After all this effort, are you sure the planet's going to be ok? Cos I am."
By the way, Paul Huxley speaks much sense on the reasons for scepticism here.