The state news agency says Hesham Kandil warned on Thursday that such fatwas could lead to "sedition and disturbance."
A day earlier, Egypt's most prominent opposition leader Mohamed ElBaradei, head of the National Salvation Front, criticized the government's silence over the edicts. A security official says ElBaradei's home has been put under observation for his protection.
In one edit, ultraconservative cleric Mahmoud Shaaban said the Front's leadership is "setting Egypt on fire to gain power, and the verdict of God's law against them is death."
Al-Azhar, the Sunni Muslim world's premier Islamic institution, and Morsi's Muslim Brotherhood group also condemned the fatwas.