Philemon 1:15

For perhaps he therefore departed for a season, that thou shouldest receive him for ever; Perhaps - speaking humanly, yet as believing that God's providence probably (for we cannot dogmatically define God's hidden purposes) overruled the past evil to ultimately, greater good to him. This thought would soften Philemon's indignation at Onesimus' past offence. So Joseph in Genesis 45:5.

Departed, [ echooristhee (G5563)] - 'was parted from thee:' a softening term for 'ran away,' to mitigate Philemon's wrath.

Receive him, [ apechees (G568)] - 'have him wholly for thyself' (note, Philippians 4:18). The same Greek, Matthew 6:2; Matthew 6:5.

Forever - in this life and in that to come (cf. Exodus 21:6). Onesimus' absence, however long, was but a short 'hour' [ pros (G4314) hooran (G5610)] compared with the everlasting devotion henceforth binding him to his master.