“Your labor is not in vain.”
Reward is for our labor. As to our place, we all get the same glory as Christ: "When [He]... shall appear," we—that is, all Christians—shall appear "with Him in glory." And Paul cannot have anything better than that. But when you come to labor, it is a very different thing, and reward is accordingly. The Thessalonians will be Paul's crown, but they will not be ours; that is clear. We know not how this will be accomplished, but in glory Paul will have them as his crown, yet he will not take away Christ's crown, for it was all grace that did it, though Christ is pleased to reward the labor when it is faithfully done, owning, not me, but the grace of God that is in me. The reward has nothing to do with motive, and it is never the motive for action in Scripture; it is the encouragement in the service.