M. Tullius Cicero Pro P. Sulla 49

[49] But when the greatest honours of your family were at stake, that is to say, the consulship of your father that wise man your father was not angry with his most intimate friends for defending and praising Sulla. He was aware that this was a principle handed down to us from our ancestors that we were not to be hindered by our friendship for any one from warding off dangers from others. And yet that contest was far from resembling this trial. Then, if Publius Sulla could he put down, the consulship would be procured for your father as it was procured, it was a contest of honour you were crying out, that you were seeking to recover what had been taken from you, in order that, having been defeated in the Campus Martius, you might succeed in the forum. Then those who were contending against you for Sulla's safety your greatest friends, with whom you were not angry. On, that account, deprived you of the consulship, resisted your acquisition of honour; and yet they did so without any rupture of your mutual friendship, without violating any duty according to ancient precedent and the established principles of every good man.