Question:
Answer:
Maybe the easiest way to explain the “how” is to just point toward the saints, who are content (and happy!) regardless of their external circumstances. As St. Paul says to the Philippians,
I rejoice in the Lord greatly that now at length you have revived your concern for me; you were indeed concerned for me, but you had no opportunity. Not that I complain of want; for I have learned, in whatever state I am, to be content. I know how to be abased, and I know how to abound; in any and all circumstances I have learned the secret of facing plenty and hunger, abundance and want. I can do all things in him who strengthens me (Phil. 4:10–13).
We often focus just on that last verse, but the preceding ones are important for contextualizing it. Paul’s not saying that everything is going to go well for him. He’s saying that he’s satisfied even when they don’t, because he’s got God. I think it’s fair to say that this is unlike the experience that those people have who have turned to something else to make them ultimately happy. (Obviously, this doesn’t eliminate other human needs: it isn’t as if the saints don’t experience hunger and thirst and the rest. It’s rather that they’re satisfied even when facing those, or other, difficulties).