Chapter 70 Then he says:

His generation who shall declare?
This was said to warn us, lest on account of His enemies and the outrage of His sufferings we should despise Him as a mean and contemptible man. For He who endured all this has an undeclarable generation; [240] for by generation He means descent; (for) He who is His Father is undeclarable and unspeakable. Know therefore that such descent was His who endured these sufferings; and despise Him not because of the sufferings which for thy sake He of purpose endured, but fear Him because of His descent.