A.T. Robertson Commentary Philemon 1:14

"but without thy mind I would do nothing; that thy goodness should not be as of necessity, but of free will." — Philemon 1:14 (ASV)

Without thy mind (χωρις της σης γνωμης). Judgment, purpose (1 Corinthians 1:10; 1 Corinthians 7:25). Ablative case with χωρις (apart from).

I would do nothing (ουδεν ηθελησα ποιησα). First aorist active indicative of θελω, I decided, I wished, decision reached (cf. εβουλομην in verse 13.

Thy goodness (το αγαθον σου). Neuter articular adjective (thy good deed).

As of necessity (ως κατα αναγκην). "As if according to compulsion." See 2 Corinthians 9:7.

But of free will (αλλα κατα εκουσιον). According to what is voluntary (Numbers 15:3). Perhaps τροπον (way, manner) is to be understood with the adjective εκουσιος (old word, here alone in N.T.), from εκων (1 Corinthians 9:17; Romans 8:20).