Matthew 5:1 Now when He saw the crowds, He went up into a mountain and sat down. His disciples came to Him, and He began to teach them saying ...Matthew 5:11 "Blessed are ye, when men shall revile you, and persecute you, and shall say all manner of evil against you falsely, for my sake. 12 Rejoice, and be exceeding glad: for great is your reward in heaven: for so persecuted they the prophets which were before you."
In this passage, JESUS speaks to His followers ... His disciples, who would soon face a range of persecutions for following Him.
The Pharisees and religious leaders were up in arms about JESUS and His following. They labored to make life difficult for them. They encouraged their Jewish families to disown them, to impoverish them. And so many did.
After JESUS' death, ressurection, and ascension, JESUS' follwers, whose numbers increased mightily, came under increasing persecution.
Stephen was the first martyred for his faith in JESUS. John's brother James followed him into glory soon after. Then JESUS' brother James. And so it went. Eventually, all of JESUS' original 12 apostles (minus Judas, plus Paul), except John, were martyred for their faith and their witness of JESUS.
The persecution of the early Jewish believers incrased in pitch until they fled Jerusalem, and then, Judea, into the surrounding areas, taking the gospel of JESUS with them.
Christians endured dire persecutions for the next 300 years, as they were put to the sword, burned at the stake, fed to the lions, etc. by way of Rome's hostility to this band of followers of JESUS.
Even today, Christians are persecuted to the point of death, in China, in the Philippines, in the Sudan, in Greece, etc., for their steadfast practice of their faith.
It is to Christians down through the ages that JESUS directed those words ...
"Blessed are ye, when men shall revile you, and persecute you, and shall say all manner of evil against you falsely, for my sake. 12 Rejoice, and be exceeding glad: for great is your reward in heaven: for so persecuted they the prophets which were before you."... for they would, indeed, be persecuted ... even as the prophets of old.