Now when Jesus saw the crowds, he went up on a mountainside and sat down. His disciples came to him, and he began to teach them.(Matthew 5:1-2)
Jesus explains at Matthew 5:12, “Rejoice, and be exceeding glad: for great is your reward in heaven: for so persecuted they the prophets which were before you.”
The world long before Jesus arrived on the scene persecuted God’s prophets. Therefore, since each one faithful to Christ and who cling tightly to his teachings and teach them to others, can expect persecution as the prophets of old did.
Their mindset is that persecution will come. It is not that they are to be happy that they will be persecuted. That is not normal. But to be happy that when it is over, they have a reward in heaven. No, not that they will go to up to heaven, but rather that the source of their reward is from and in heaven. What is that reward? Everlasting life in God’s kingdom when it comes down to the earth.