On 5 September 1528 he was nominated Lord High Treasurer on the downfall of the Earl of Angus, replacing Archibald Douglas of Kilspindie.
James V also gave Robert a tenement in Edinburgh close to a house of Andrew Moubray that had been given to Kilspindie.
[1] Knowing that the Abbot of Holyrood was on the point of death, Robert, according to George Buchanan, wagered a large sum with James V that he would not present him to the first vacant benefice, while the King, quite well aware of what he referred to, accepted and won the wager.
On 23 June 1539 he was admitted to the see of Ross, and shortly afterwards received in commendam the abbacy of Fern, the dilapidated state of which his wealth was expected to repair.
On the death of James V he was appointed one of the lords of the council to the governor, the Earl of Arran, when he joined in opposing the treaty of peace with England.