The Bishop of Thunder Bay says he's surprised but not shocked by the resignation of Pope Benedict XVI.

Fred Colli said the pope must have recognized he no longer has the stamina that he needs to do his job and it was courageous of him to step down.

Thunder Bay Bishop Fred Colli said the pope's job is one that requires great stamina. (Supplied)

“The pope's job is something that takes a lot of energy and a lot of stamina,” Colli said.

“And no matter how old you are, you have to continue on with the work that the pope must do. And I could see that it was probably wearing on him quite a bit.”

Bishop Colli said the pope will be best remembered for being a great teacher .

“He implemented things like the compendium to the Catechism. He encouraged a greater learning of the Catholic faith. Being a teacher is really his norm because he is a professor."

'He did a lot more' than what met the eye

Colli also remarked on the pope’s “outreach to other Christian communities like the Anglicans, and the Orthodox teachers, his desire to work with them, and even to sort of welcome them to the Catholic fold if they were willing to."

It’s not fair to criticize the pope for his response to sex abuse scandals in the Catholic Church, Colli said.

"When they start to examine the positions he was in and the way he responded to the abuse scandals ... he was very forceful even though people think, well, he should have been more forceful,” he said.

Colli added that “He implemented many rules and regulations within the church to counteract this kind of abuse by a few priests. He did a lot more than what he appeared to do."

Growing the church’s communication with the wider world will also be the pope’s legacy, Colli said.

"He is the first pope to be on Twitter, so he opened up some of the communication areas in the church, and saw the need for this global communication connection with the Vatican and the church and the world."