M. Tullius Cicero Divinatio in Q. Caecilium 61

[61] And just think how great is the difference between my opinion and yours. You, though you are in every respect inferior to me, still think that you ought to be preferred to me for this one reason, because you were his quaestor. I think, that if you were my superior in every other qualification, still that for this one cause alone you ought to be rejected as the prosecutor. For this is the principle which has been handed down to us from our ancestors, that a praetor ought to be in the place of a parent to his quaestor; that no more reasonable nor more important cause of intimate friendship can be imagined than a connection arising from drawing the same lot, having the same province, and being associated in the discharge of the same public duty and office.