Literal translation
to play the clerk and the chaplain
Meaning
to ask the questions and answer them oneself
Explanation
To ask the questions and give the answers oneself, that is, to talk without letting anyone else speak. The image draws on the roles of the capélan, priest in Provençal, and his altar server during Mass: one speaks the sacred words, the other answers. Whoever plays both parts thus dominates the whole exchange. The word capélan, carried into regional French, took on a rather mocking tone there, fitting for a lower Provence long known for its secular streak, where poking fun at religion came easily.