Have you ever met someone who complains all day long? "This game is boring," "I don't like this food," "My brother is so annoying." That person is wearing invisible gray glasses that only let them see the bad side of everything.
But Jesus wants us to wear a different pair: the gratitude glasses! With these glasses, even when something doesn't go the way you wanted, you can find something good in it.
For example: if it starts raining and you can't play outside, instead of complaining, you can think, "How cool, I get to build a blanket fort in the living room!" The situation didn't change, but the glasses you're wearing did, and that changes everything you feel.