Our Lord’s advice against patching an old cloth garment with a piece of new cloth, and against pouring new wine into old wine skins could be taken as a warning against letting laziness lead us into half-way measures.
Like, you need to patch up a rent in your old jeans; and rather than search for something just as old, you stitch a square of new denim over the tear; only to find at the first washing that the new patch has shrunk, pulling away on all sides.
Or, you have pressed two gallons of grapes, and you are looking for a container, and you see a discarded wine skin from last year. And even though you have heard that the old wine skin hasn’t the "give" left to expand with the fermenting grape juice, you chance using the old skin one more time. Three days later you find that the juice has gone explosive, ripping the wine skin, and spilling out all over.
We should discipline ourselves against taking stop-gap measures.
Our Lord liked using such images from the house and garden, and instead of just leaping to their moral applications, we should get firm imaginative holds on the images themselves. Like, on the bus one day last week I sat next to a thirtyish fellow who was working with needle and thread sewing up a rip in his chinos; and it made me resolve to do little jobs the way they should be done.
Then, fifty years ago in Korea the cook came up from market day with word that a woman from the hills had brought in a large apron full of wild grapes. I went with her to buy them, then we pressed them, stowing the murky juice away in an empty kimchi pot. Lifting the clothe from over it two weeks later, we saw it was a beautiful clear ruby. People warned me that it was still fermenting, but I gathered old bottles, corking up a dozen of them filled with the new wine, stowing them under my cot.
The grape juice hadn’t completed its fermenting; and in a version of the new-wine-in-old-wine-skins disaster, at midnight the bottles started exploding their corks at the underside of my mattress.
That isn’t what Jesus was warning against, but he is lenient about how we use his parables.