Pennant's deal with Stoke runs to January.
He told The Sentinel: "I enjoyed my time in Spain, but unfortunately the manager who brought me over got the sack and the new manager wanted to be more defensive.
"It was difficult for me to get into his plans and not speaking the language made it difficult.
"It's nice to come back, have a team meeting and know what's being said and know what instructions I have, rather than looking to the sky wondering what he's saying.
"The gaffer here has given me a good talking to and made it clear what he expects - to play with passion and fit in with everybody else."