Scholars unanimously explain that Paul's use of the word 'robbed' is a powerful metaphor, not a literal confession of theft. He uses this strong, military-style term to highlight an unusual situation: he was receiving financial support ('wages') from poorer churches, like those in Macedonia, in order to minister to the wealthier Corinthians for free. This was a reversal of the normal principle that a minister is supported by the people he serves.