"Beware the ides of March" (I:2:ln18 ). The soothsayer is trying to warn Caesar about the ides of march. But Caesar just keeps on walking.
Act lV: Sc
Cowards die many times before their deaths; The valiant never taste of death but once. (II:2:ln32/33) Caesar explains to his wife that even if he does die at least he didn't die a coward. He says this because he thinks that if you run away from your problems you die a little bit each time.
Act V: Sc
What touches us ourself shall be last served. (III:1:ln8) Caesar explains that you should put others before your self. He manly says it to make himself look good.
To tell thee thou shalt see me at philippi then. (IV:3:ln283) Caesars ghost comes to Brutus to tell him he will die at the battle. When Brutus hears this he packs up camp and takes his army to philippi. Only to kill himself in the long run.
This was the noblest Roman of them all. (V:5:ln 68) Antony says that even though Brutus killed his best friend he was still a very noble man.