My dad grew up in a house where Norwegian was spoken frequently. He also spent at least one of his childhood summers with an aunt and uncle living in Norway.
Living stateside, even if Norwegian was the only thing spoken in his home, he still had exposure to plenty of English (friends, school, etc.). Making the transition for a summer to an environment where he was totally surrounded by people speaking a different language, he could speak English and some people would still understand him, but he eventually started switching over to speaking Norwegian because it was just easier to communicate that way. He said the weirdest thing was how, after doing this for awhile, he began to think in a different language.
This is like what Christians are faced with in their lives here on Earth. Though this life figures prominently in our thinking and what we spend our attention on, this place is really only our temporary home. Even though Christians are citizens of Heaven, we’re deeply immersed in a foreign culture that shouts loud enough to drown out the values and ideals of our eternal home. Without maintaining connections to God-approved values in the form of Bible readings, prayer, Bible teachings, and Christian fellowship, it’s easy to be overcome by the persistent influence of this world.
Even though we’re only here for a brief lifetime, it’s important to maintain these connections to “back home” where we’ll be spending the bulk of our time. We’re in this world, but not of it. Don’t get too attached to the things your home culture places no value on, and don’t let your thinking be overtaken by the culture we’re only visiting. We’re going home someday, after all.