Biblical scholars have been waiting for a clear shot at M.910 since the early '60s.
The president announced a three-month state of emergency after two bomb blasts on Coptic churches killed 49.
No group has yet claimed responsibility but the Islamic State has stepped up attacks against Christians in Egypt.
After years of slow but steady decline, Christians are being driven from the Middle East by ISIS.
A photojournalist captures the mourning rituals for 21 Egyptian Coptic Christians beheaded by ISIS in Libya.