Silva made his reasons known Thursday during a media call to promote his upcoming 205-pound bout against Stephan Bonnar at UFC 153 on Oct. 13 in Rio de Janeiro.
"There's always been a lot of talk about me moving up to 205," said Silva, who successfully has defended his title a UFC-record 10 times. "I know (UFC president) Dana (White) has talked about it and all the fans have talked about me moving up and facing Jon Jones.
"But it's something I've never wanted. I won't be pretentious and say that I'd want to move up, especially because there are other guys in the weight class and on our team like Rafael Feijao (Cavalcante) and (Antonio Rogerio) Minotoro Nogueira, guys who could potentially face Jon Jones in the future.
"What got me this far is that I'm grounded; my weight class is 185 and I'm 37 years old. I feel I need to be honest and continue to build what I've built and that is to keep defending my belt at 185."
Silva previously stated his respect for Jones is the reason he would not move up a weight class to fight him. That explanation, however, gave hope to mixed martial arts fans that a bout with Jones remained possible.
Hopes of a Silva-Jones bout were heightened in recent months by talk of another high profile fight between Silva and welterweight champion Georges St Pierre. Each fighter has expressed a desire to fight one another.
That fight could happen next year if St. Pierre defeats interim 170-pound titleholder Carlos Condit at UFC 154 on Nov. 17 in Montreal.
After defeating Chael Sonnen by second-round TKO on July 7, Silva said he would not return to action until 2013. But twice in a little more than a month he has offered to fight in an effort to save a UFC event.
He told UFC officials in August that he would fight on short notice to help save the promotion's Sept. 1 event in Las Vegas. But that event, UFC 151, was canceled after Jones refused to face Sonnen on eight days' notice.
Silva agreed last month to fight Bonnar after UFC featherweight champion Jose Aldo was forced to withdraw from his main-event bout with former lightweight titleholder Frankie Edgar. Aldo was unable to compete because of a foot injury.
With Aldo out, Edgar was taken off the UFC 153 card.