Sora was facing off against Riku his best friend/brother figure, wielding souleater in Hollow Bastion. He had Donald and Goofy backing him up and his speech was just him telling Riku that the keyblade is not "all that" and not ultimate power and that "his friends are his power." Riku being one of these friends
Ven is facing off against Vanitas who is pretty much Ven's arch-nemesis and cause of most of Ven's pain through out BBS. Vanitas was not only wielding the X-Blade in which Vanitas and MX had told TAV how devestating pwerful it was, but was also facing each other off within their consiousness, their heart, their Awakening Station place thingy. Vanitas threatened to end Ven, then the worlds, and then end Terra and Aqua whom he cares about more than himself. Ven not willing to let that happened told Vanitas wielding possibly the most ridiculous weapon, that he doesn't care how much power Vanitas wields around and throws at him that "His friends are his power" meaning usin that alone he will defeat his darkness at the cost of his own life for his friends.
Hmmmmm.....