It's crystal clear from these early stories that Theseus is destined to rank right up there with all of his fellow heroes. Like Perseus and Heracles, he's a demigod, meaning that at least one of his parents is immortal. Even though he's a little different in that he's got a mortal father as well, the blood of Poseidon runs strong in Theseus, pumping him full of super strength and skill.
We also see that he's similar to his buddy Heracles in that he performs several "labors" to make his name. His labors are small fry compared to the feats of Heracles, but still more than any ol' Regular Joe could handle. The six bandits that Theseus kills on the way to Athens remind us a lot of the Twelve Labors that Heracles must perform. The series of villains that Theseus slays on the way to Athens is even sometimes called the Labors of Theseus. So, just like Heracles, Theseus proves himself by conquering a whole string of enemies.