In the last days (in the end time) there will be scoffers [who seek to gratify their own unholy desires], following after their own ungodly passions. It is these who are [agitators] setting up distinctions and causing divisions--merely sensual [creatures, carnal, worldly-minded people], devoid of the [Holy] Spirit and destitute of any higher spiritual life.
It doesn't take a scoffer to "set up distinctions". They, also most accurately called agitators in the Amplified Version above, influence us and cause us to do the same. This verse really jumped out at me after hearing a sister-in-the-Lord come to the conclusion that her brothers and sisters in Christ are against her because she is of a different skin color. She has set up distinctions to her own misery.
We marginalize the agitators, (racial and otherwise), because they are so intellectually, morally and spiritually bankrupt, but their influence, as it turns out, is not marginal. They don't just play with the emotions of the weak-minded. They corrupt everyone within earshot. Not even members of the Body of Christ are exempt since they obviously have an evil influence on us.