Matthew 5:12

Protestant: Salvation is a gift, and therefore free, unmerited. It can never be a reward, for that would make Christ's suffering on the Cross a joke.

Catholic: Sacred Scripture says that eternal blessedness in heaven is the reward for good works performed on this earth, and rewards and merits are correlative concepts.

In Mt 5:12 Jesus promises rich rewards In heaven to those who, for his sake, are scorned and persecuted. In Mt 25:34 ff, the Judge of the World decrees eternal reward for the just on the ground of their good works.

In Matthew 5:12, Jesus was talking to REDEEMED/JUSTIFIED men. Notice in 5:1, From among the crowds, His DISCIPLES came to Him. Disciples are those who are learners or students of Jesus. They become one because they believe in Him.

In Matthew 25:34, consider when this scenario takes place. Will this takes place after the great tribulaton or before. Will this takes place after the rapture or before. Relate this to 1st Thessalonians 4:13-18. This is to make clear why these men are rewarded by their good works.

Catholic: What you claim is hard teaching. Surely, Jesus did not come to the world to save ONLY Jews, and among the Jews, only BELIEVERS. Surely, Jesus came for all mankind, including future human beings, not only that motley group who were so fortunate to have been there.

In the Beatitudes, Jesus was teaching mankind how to get to heaven, which is open to all whose religious dispositions and moral conduct meet the demands which Jesus lays down. The meek, the peacemakers, the pure in heart, etc – these are not different kinds of people, but different demands made on everyone who wants to be a disciple of Christ. (Navarre Bible)

Similarly, salvation is not being promised to different groups in society- e.g., believers only, but to EVERYONE who strives to follow the spirit and to meet the demands contained in the Beatitudes.