Albert Barnes 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. That is, "I had a strong desire to see you, to assist you, and to enjoy your friendship; for you are my hope and joy, and my absence does not arise from a lack of affection." The meaning, when he says that they were his "hope," is that their conversion and salvation was one of the grounds of his hope of future blessedness. It was an evidence that he was a faithful servant of God and that he would be rewarded in heaven.

Or joy. The source of joy here and in heaven.

Or crown of rejoicing. The marginal reading, as in Greek, is glorying; that is, boasting or exulting. The allusion is probably to the victors at the Grecian games, and the sense is that he rejoiced in their conversion as the victor there did in the garland which he had won. (See the notes on 1 Corinthians 9:24–27).

Are not even ye. Or, will not you be?

In the presence of our Lord Jesus Christ at his coming. "When the Lord Jesus appears at the end of the world, then our highest source of happiness and honour will be your conversion and salvation." Then their salvation would be a proof of his fidelity. It would fill his soul with the highest happiness that he had been the means of saving them from ruin.