Background information: A bull is a papal decree, or statement, issued by a pope. This one condemns the ideas of Martin Luther.

Therefore we can, without any further citation or delay, proceed against him to his condemnation . . . as one whose faith is notoriously suspect and in fact a true heretic with the full severity of each and all of the above penalties and censures. . . . It is our hope, so far as in us lies, that he will experience a change of heart by taking the road of mildness we have proposed, return, and turn away from his errors. We will receive him kindly as the prodigal son returning to the embrace of the Church.

If Luther “experience[s] a change of heart,” what will happen in return?

He will be welcomed back into the church.
He will be condemned as a heretic.
He will face penalty and censure.
He will reject the road of mildness.