After the very personal comments which Paul has made since verse 12 which were designed to appeal to the affections of the Galatians, he now turns again to arguments from Scripture. ‘Tell me’ – a very lively way of writing, for though he is writing and not speaking face-to-face, his words invite a response to get them thinking.
This mixture of doctrine and personal appeal gives us an example of how to win back those who are being carried away by error. Too much doctrine without affection will make us appear to be indifferent to them as people and only interested in winning the argument. But too much emotional appeal without anything substantial will convince them that we have no Scriptural basis for what we say and will leave them unconvinced. Men will not allow themselves to be persuaded about things so important, unless there is something substantial for them to rest on.