Where John Pym, leader of the Parliamentary opposition, differed from Clarendon and most of his own colleagues was in recognising Charles would not keep commitments he considered forced on him. An example was his annulment of the 1628 Petition of Right, while he and his wife Henrietta Maria openly told foreign ambassadors any concessions were temporary, and would be retrieved by force. It was also consistent with his approach in the Bishops Wars, when he only agreed peace terms with the Scots in 1639 to provide time for another attempt in 1640.