The date of his promotion to the abbacy is uncertain.
When James Beaton was translated to St Andrews in 1522 he resigned the rich abbacy of Arbroath in his nephew's favour, under reservation of one half of the revenues to himself during his lifetime.
The terms were, among other things, his appointment to the rich abbacy of St Denis and his restoration to his other benefices with the payment of arrears.
The first outcome of the new connexion was his appointment to the abbacy of Aberbrothock by the queen regent, before her marriage, probably in June 1514.
He was now firmly established in the favour of the king, who gave him successively the abbacy of St Severin, in the diocese of Poitiers, the office of almoner to the dauphiness, and in 1685 the bishopric of Lavaur, from which he was in 1687 promoted to that of Nimes.