After hearing about stories about how young people are diagnosed with a terminal illness and they only have months to live, it got me wondering. There is no guarantee of a long healthy life, no idea if the next week could be anyone's last days on Earth if it's because a car accident or anything else.
How much time have we probably wasted, and not spent it doing the things we love?
I will be changing the way I live, treating every month like it could possibly be my last, I think that will help push me to live life to the fullest and even live more for God. But I haven't been doing that in the past, I have been waiting and planning on doing things much later, but we don't know how much time we will have on Earth.
This sounds like the latin saying of "carpe diem", or "seize the day". Oftentimes, it is taken to mean to enjoy your life to the fullest, whatever that may mean to you personnally and subjectively. That interpretation isn't entirely christian, since the purpose of life is not to be merely "enjoyed", especially when the pleasures envisioned are often sinful in nature. Rather, I think, we should take it to mean that our time here on Earth is precious and that we should seek to live it meaningfully and usefully or wisely. As Christians, we are here to grow in holiness (sanctification) and encourage others to either embark on the journey (outreach) or to keep at it faithfully (exhortation and teaching). After all, we are here to serve God and our Lord and King Jesus. We belong to a spiritual nation, a kingdom, and it will eventually permanently replace all those presently existing. Thus, we seek to invite others to join it, so they may live forever with us in this promised land. Our end, as Christians, is eternal life. We wish that end for everyone and we wish those that have it to retain it (faithfulness and perseverance as opposed to apostasy). A life well lived is not necessarily a life pleasantly lived. Just think of all the martyrs who suffer persecution or even executions. They are nonetheless the greatest of heroes and deserving of all the spiritual honors they will receive in Heaven, as promised to us by Jesus. That's because of God's generosity. A life well lived is a life admirably lived. After all, we are called to be witnesses, as Jesus said, of the light and the truth.
Beyond that, Jesus did say that we should await his return incessantly and eagerly and indeed act accordingly. We should remain zealous, full of ardor and fully faithful and trusting while we wait. That includes studying and applying his teaching in our lives and telling and helping others do the same in theirs. He also said that we shouldn't seek to amass fortunes here on Earth but spiritual riches in Heaven, which are eternal and indestructible (Matthew 6:19-21 and Luke 12:15-21). Everything here on Earth will be lost and destroyed sooner or later.
I've had the same thoughts as you and that's what I got out of it so far. I probably could say more, but anyways. One thing I would add is this : don't pressure yourself too much either to live maximally or perfectly. That can be a burden and take a toll on someone. There is balance to be found between zeal and apathy. I guess try your best. If you trust in Jesus, his sacrifice for you and his promises, then you are forgiven by God and approved by him, meaning your life is already satisfactory in his eyes. Don't forget you'll have eternity to enjoy after that! Whatever fun thing you don't do now, you'll have infinite opportunity to do later! It puts things in perspective! And whatever fun you might have here, it'll be all the more enjoyable there, since it'll be perfect!
There is certainly solace to be found in the knowledge of your own eternal security! Whatever happens in the here and now, you are safe and that forever! God carefully and watchfully holds our lives in his hands.