Shawn rightly asks what kind of things I'm referring to by suggesting that we "grow olive trees," so here are some examples.
On a personal level, I'd suggest homeschooling, becoming more active in the outreach ministries of your church (or starting one if it doesn't exist), and simply taking steps to spend more time with those you love. The material world is, after all, going to have some "extensive renovations" in the end times, if I read the Scriptures correctly, and it's the souls I reach for Him that will survive.
Even in view of catacylismic end times, however, I think it's still worthwhile to "plant some olive trees" in the physical world, as it speaks to permanence in a world that values the fashion of the day . In California or the Mediterranean, that might mean an actual olive tree or two.
But it's not just about trees, but about everything in life. Some "olive trees" in my home include the cast iron my grandmother used as a child, tools that my grandfathers used, hardcover books, real wood furniture (new & old), and even using better quality siding and shingles on the house. If you're spending the time to put it on, might as well make it last, no?
And even an example from government; the new highway to my town has the concrete poured about 15-18" thick, instead of more typical 4-6" asphalt or 6-10" concrete. Hopefully this will keep it in good shape for a few more years than some of the parchment-like pavement they've been pouring for the past few decades.
I'd have to guess that most of this does nothing to qualify a project as "sustainable", at least acccording to the "politically correct," but I think this is a more worthwhile approach.
What's it all about? - What's it all about? Algorithm.*What's it all about, Alfie?* *Is it just for the moment we live?* *What's it all about when you sort it out, Alfie?* *Are we...
49 minutes ago