24 Or “I am encouraging …”
25 Grk “my child whom I have begotten.” The adjective “spiritual” has been supplied before “father” in the translation to clarify for the modern reader that Paul did not literally father a child during his imprisonment. Paul’s point is that he was instrumental in Onesimus’ conversion while in prison.
26 During my imprisonment. Apparently Onesimus became a believer under Paul’s shepherding while he [Paul] was a prisoner in Rome.

In other versions

I appeal to you for my child, Onesimus, whose father I became in my imprisonment.

that I appeal to you for my son Onesimus, who became my son while I was in chains.

appeal to you for my son, Onesimus. I became his father while I was in chains.

I appeal to you to show kindness to my child, Onesimus. I became his father in the faith while here in prison.

I am appealing to you concerning my child whom I became the father of during my imprisonment, Onesimus.

I beseech thee for my son Onesimus, whom I have begotten in my bonds:

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