"I didn't do it the right way - I was a naive young man and made the wrong decision," said the 28 year old midfielder. "I thought I was making the right choice but you can't act like that.
"I apologise for the way I went about it because I love being here, I love playing for this club.
"I thank them for what they did for me while I was here and it's good to be back. Hopefully I can replay them by coming back and performing for them."
Bentley last featured for his parent club in November 2010 and has taken in loan spells with West Ham, Birmingham and Russian outfit Rostov, but insists he does not regret moving to White Hart Lane.
"Sometimes you make decisions, I'm just a young man whose made a mistake in making that decision to move," he added. "But it's not a regret, it's a decision I made and I wanted. It just didn't work out.
"It was down to four or five things, a few things. It just didn't work out and I don't think it was anything to do with football."