New International Version:
See what large letters I use as I write to you with my own hand!
Holman Christian Standard Bible:
Look at what large letters I use as I write to you in my own handwriting.
Darby Bible Translation:
See how long a letter I have written to you with my own hand.
This verse appears straight after a serious discussion about living our Christian lives “in the Spirit” and not “sowing to the flesh,” and about “doing good to all, particularly members of the family of faith.” It is then followed by a reprise of Paul’s earlier points about circumcision, leading to boasting “of your flesh.”
Hardly an appropriate place to stick a comment about his handwriting, but most translations have some reference to large writing or a long letter, neither of which fit very comfortably here. And the resulting verse adds nothing to the discussion, being a complete non-sequitur.
What he is actually doing here is bringing to their attention the weightiness of the discussion and its immediate application to the Galatians (and to us). We must deny our flesh in all its forms, particularly with reference to circumcision, or we will “reap corruption” and shipwreck our faith.
The Mouse Companion Version (MCV):
See how serious is this letter that I’ve written to you.
The idea that he used his own hand to write is silly, as nothing could be written in those days without using somebody’s hand, but since ‘hand’ also means ‘power’ or ‘agency’ he’s not even differentiating this letter from others he’s written using a scribe and not his own hand, he simply means it’s a letter from him, personally.
Bless you folks, Geoff >ᴥ<