A very close friend of mine found this.

During the time of the Roman Empire, Cicero had his own beliefs on friendship.

Cicero believed that in order to have a true friendship with someone there must be all honesty and truth. If there isn’t, then this isn’t a true friendship. In that case, friends must be one hundred percent honest with each other and put one hundred percent of their trust in the other person.

Cicero also believed that for people to be friends with another person, they must do things without the expectation that their friend will have to repay them.

He also believes that if a friend is about to do something wrong, and something that goes against your morals, you shouldn’t compromise your morals. You must explain why what they are going to do is wrong, and help them to see what the right thing to do is, because Cicero believes that ignorance is the cause of evil.

Finally the last thing that Cicero believed was that the reason that a friendship comes to an end is because one person in that friendship has become bad."