Do Not Love The World

I'm studying this verse:
Do not love the world nor the things in the world. If anyone loves the world, the love of the Father is not in him.

At what point would we say we are loving the world? What is the line? And how do we know when it is crossed?
I think the verse following it gives the 'general guideline' of what is of the world. "For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world." 1Jn 2:16.

I think the 'line' is hinted at in 1Co 7:31 "And they that use this world, as not abusing it: for the fashion of this world passeth away." to which Matthew Henry comments "As not abusing it - καταχρώμενοι katachrōmenoi. The preposition κατα kata, in composition here has the sense of “too much, too freely,” and is taken not merely in an intensive sense, but to denote evil, the abuse of the world. It means that we are not to use it to excess; we are not to make it a mere matter of indulgences, or to make that the main object and purpose of our living. We are not to give our appetites to indulgence; our bodies to riot; our days and nights to feasting and revelry."

I was reading Matthew Henry's commentary on 1 Jn 2:16:
The meaning is, that we are not to fix our affections on worldly objects - on what the world can furnish - as our portion, with the spirit with which they do who live only for this world, regardless of the life to come. We are not to make this world the object of our chief affection; we are not to be influenced by the maxims and feelings which prevail among those who do. Compare the Rom 12:2 note, and Jam 4:4 note. See also Mat 16:26; Luk 9:25; 1Co 1:20; 1Co 3:19; Gal 4:3; Col 2:8.

Neither the things that are in the world - Referred to in the next verse as “the lust of the flesh, the lust of the eyes, and the pride of life.” This explanation shows what John meant by “the things that are in the world.” He does not say that we are in no sense to love “anything” that is in the material world; that we are to feel no interest in flowers, and streams, and forests, and fountains; that we are to have no admiration for what God has done as the Creator of all things; that we are to cherish no love for any of the inhabitants of the world, our friends and kindred; or that we are to pursue none of the objects of this life in making provision for our families; but that we are not to love the things which are sought merely to pamper the appetite, to please the eye, or to promote pride in living. These are the objects sought by the people of the world; these are not the objects to be sought by the Christian.

If any man love the world ... - If, in this sense, a person loves the world, it shows that he has no true religion; that is, if characteristically he loves the world as his portion, and lives for that; if it is the ruling principle of his life to gain and enjoy that, it shows that his heart has never been renewed, and that he has no part with the children of God. See the Jam 4:4 note; Mat 6:24 note.
Interesting question. I'm not sure. Isn't it like loving anything Ungodly?
Gossiping, drugs, sex between unmarried folks, getting drunk. Christians should stay away from such things.

I think some can avoid the observable sins and outwardly look "good" but still be rather attached to the world in a personally comfortable sort of way. Perhaps the most extreme example of this would be the Pharisees who were likened to whited sepulchres?