Book four of The Shifa of Qadi Iyad has the legal ruling pertaining to the case of Shaykh Hamza Yusuf. Imam Qadi Iyad is a 5th Century Islamic Jurist. We pray Shaykh Hamza reads the relevant passage and retracts. For if defend is a synonym of explain, then explain is a synonym of defend. That would mean by explaining Dante, a person is defending Dante and by defending he is explaining. That would not make any sense, unless, explain would mean "in favour of".
This whole incident should not encourage Muslims to read or purchase copies of Dante's "Inferno" or Rushdie's "Satanic Verses" as such literature should be avoided.