James 1:2-4 Count it all joy, my brothers, when you fall into various temptations, knowing that the testing of your faith produces endurance. Let endurance have its perfect work, that you may be perfect and complete, lacking in nothing.

Romans 5:3-4  . . . we also rejoice in our sufferings, knowing that suffering produces perseverance; and perseverance, proven character; and proven character, hope

(‘Hope’ refers to our eternal reward.)

This fits perfectly the teaching of Jesus. He told us to rejoice when people give us a hard time. Why? Because rejoicing gives us a false but much-needed emotional high? No, ‘because great is your reward in heaven.’

Matthew 5:11-12 Blessed are you when people reproach you, persecute you, and say all kinds of evil against you falsely, for my sake. Rejoice, and be exceedingly glad, for great is your reward in heaven. . . .

Ephesians 5:20 giving thanks always concerning all things in the name of our Lord Jesus Christ, to God, even the Father(Emphasis mine)