The 41 year-old signed with the Portuguese giants just days after his deal with Fluminense expireed.
The veteran put pen to paper on his Porto contract yesterday and this morning responded to critics at home in Brazil regarding his choice.
He posted: "I'm here to clarify some things said today, taken out of context by evil minds, by people with bad intentions.
"I'm also here to express how much I love Fluminense, both myself and the Silva family. To thank, in particular, the president for his commitment and everyone who made it possible. We will carry Fluminense in our hearts for the rest of our lives."
Silva also stated: "My return to Europe brings me closer to my family. My children are experiencing special times and I miss them. I would like to be closer to them; I've already missed so many special moments..."