John Calvin Commentary Philippians 1:26

"that your glorying may abound in Christ Jesus in me through my presence with you again." — Philippians 1:26 (ASV)

That your glorying. The expression which he uses, ἐν ἐμοί, I have translated de me (concerning me,) because the preposition is used twice, but in different senses. No one, assuredly, will deny that I have faithfully conveyed Paul’s meaning. The translation given by some—per Christum, (through Christ),—I do not approve of.

For in Christ is used instead of Secundum Christum, (According to Christ), or Christiane, (Christianly), to indicate that it was a holy kind of glorying. For otherwise we are commanded to glory in God alone (1 Corinthians 1:31).

Therefore, malicious people might raise the objection to Paul: “How is it permissible for the Philippians to glory concerning you?” He anticipates this slander by saying that they will do this according to Christ—glorying in a servant of Christ, with a view to the glory of his Lord, with an eye to the doctrine rather than to the individual, and in opposition to the false apostles, just as David, by comparing himself with hypocrites, boasts of his righteousness (Psalms 7:8).