Summary: They know the way they are living, so to put a Christian down makes them feel better about themselves.
Strife-bitter conflict or rivalry: bitter and sometimes violent conflict, struggle, or rivalry
Hatred is inescapable. Sooner or later, despite all our precautions, someone, somewhere will hate us. And if we're followers of Jesus, it will happen sooner rather than later.
In John 15:18-16:4,
Verse 18-The world can simply be defined as constituting those who don't believe in Jesus Christ.
What Jesus wants us to know is that before anyone ever hated us, he or she hated Jesus.
He lets us know that the world's hatred toward us is, in reality, hatred toward him.
Jesus then lays before them a condition that is contrary to fact.
Verse 19-If they were of the world (and they are not), the world would be loving them.
We often expend much effort trying to get the world to love us, or at least not to hate us.
The effort is not only wasted, it's misguided. It's wasted because the world will never really love us.
In order for it to love us, we have to act like people we are not.
Jesus says that " I chose you." The construction emphasizes the pronoun "I." Jesus, then, is taking responsibility for the world's hatred toward us. When the world hates us, it's not our fault, so to speak. Jesus chose us.
Verse 20-Earlier, in John 13:16, Jesus said that "a slave is not greater than his master." He did so then to show them that they should serve just as he did. Here he applies that same saying to persecution.
Because they are followers of him, and because he experienced persecution, they will experience it as well. Clearly, this is something we should expect. If they persecuted Jesus, and they did, they "will" persecute us.
Verse 21-He tells the disciples that people of the world will do "these things" - meaning, acts of persecution - to them "for my name's sake."
As an ambassador represents the "name" of his or her country, we represent the "name" of Christ.
If they hate the country, they'll hate the ambassador.
It's as if Christ's name were stamped on us. The world sees the name and gets angry.
Verse 22-25-As Jesus says, the world is also angry because it doesn't know the Father. If it had a relationship with the Father, it would know that Jesus was sent by the Father, and it would hate neither Jesus nor his disciples.
They know the way they are living, so to put a Christian down makes them feel better about themselves.