John Calvin Commentary 1 Thessalonians 2:19

"For what is our hope, or joy, or crown of glorying? Are not even ye, before our Lord Jesus at his coming?" — 1 Thessalonians 2:19 (ASV)

For what is our hope? He confirms that fervent desire, which he had mentioned, since he has his happiness, in a way, treasured up in them. “Unless I forget myself, I must necessarily desire your presence, for you are our glory and joy.” Furthermore, when he calls them his hope and the crown of his glory, we must not understand this to mean that he gloried in anyone but God alone, but because we are allowed to glory in all God’s favors, in their proper place, in such a way that God is always our ultimate aim, as I have explained more fully in the First Epistle to the Corinthians.

We must, however, infer from this that Christ’s ministers will, on the last day, according to how they have individually promoted His kingdom, be partakers of glory and triumph. Let them therefore now learn to rejoice and glory in nothing but the successful outcome of their labors, when they see that the glory of Christ is promoted through their agency.

The consequence will be that they will be motivated by that spirit of affection for the Church with which they ought to be. The particle also denotes that the Thessalonians were not the only persons in whom Paul triumphed, but that they held a place among many. The causal particle γάρ, (for), which occurs almost immediately afterwards, is used here not in its strict sense, by way of affirmation—“assuredly you are.”