John, an apostle wrote in 1 John 4:15-17:
“Do not love this world nor the things it offers you, for when you love the world, you do not have the love of the Father in you. For the world offers only a craving for physical pleasure, a craving for everything we see, and pride in our achievements and possessions. These are not from the Father, but are from this world. And this world is fading away, along with everything that people crave. But anyone who does what pleases God will live forever.”
This does not mean for one minute that we should not enjoy our lives and living to the fullest. We not only can enjoy things in our world like the joy of nature, all things of beauty, pure music and art, family and friends and brothers and sisters. What I think John is saying is to not to be taken in by world values and ungodly pleasures or to chase after that which is not of the Kingdom of God. As long as we are here we are to enjoy it and make a difference every way we can.
“Christians should live in the world, but not be filled with it. A ship lives in the water; but if the water gets into the ship, she goes to the bottom. So Christians may live in the world; but if the world gets into them, they sink.” (D.L. Moody, 1837-1899 evangelist and publisher).
“Those who love their life in this world will lose it. Those who care nothing for their life in this world will keep it for eternity.” Jesus