Jamieson, Fausset and Brown on 1 Corinthians 4:12

12. working with our own hands--namely, "even unto this present hour" (1Co 4:11). This is not stated in the narrative of Paul's proceedings at Ephesus, from which city he wrote this Epistle (though it is expressly stated of him at Corinth, compare Ac 18:3, 19). But in his address to the Ephesian elders at Miletus (Ac 20:34), he says, "Ye yourselves know that these hands have ministered unto my necessities," &c. The undesignedness of the coincidence thus indirectly brought out is incompatible with forgery.