Do not love the world or the things of the world.
If anyone loves the world, the love of the Father is not in him.
For all that is in the world,
sensual lust, enticement for the eyes, and a pretentious life,
is not from the Father but is from the world.
Yet the world and its enticement are passing away.
But whoever does the will of God remains forever.
1 John 2:15-17
It is with the understanding that if we love the things of the world we don't have love for the Father in us. It's true! Thinking back to the years when possessions were a focus in life, and the need to have things, really did put God on the back burner. So many times we think of the things we need and want without thought to God and the gift he gives to us. It is rare when a person thinks and asks God for the things they need.
In the reading today it is spoken about sensual lust, enticement for the eyes and a pretentious life. Back then they wore more covering than we do today, so lust is rampant, enticement is constant and we live in a way that we have pretty much everything. As they say all this stuff in the world shall pass away, and how true that is, because possessions are nothing unless well preserved and even then eventually it passes away. But who ever does the will of God remains forever.
In this we read of the many who have come before us, in the lives of the apostles, martyr, and saints who have done the will of God. They will outlast any possessions we will ever have. And knowing this we still want the things of the world, rather than a Holy life.