Also there are great books by H.H Pope Shenouda III on this topic of Protestant thought infiltrating Egypt.
The three I can remember that he responds to protestant claims are:
1- Against the Heresy of Salvation in a moment.
2- Comparative Theology
3- Salvation - An Orthodox Concept
Most of these books can be found here:http://www.agape-bookstore.com/default.php?cPath=15&sort=3a&page=1
Also, a general note to tell your parents and the Protestant Egyptian is that you have studied the history of your Christian faith and you wish to practice it as the first few generations of Christians did; that was Orthodoxy. If Protestantism is correct, then God allowed his Church to be deceived for 1500 years until Martin Luther came along, denying the promise of the Lord:
Mat 16:18 "And I tell you that you are Peter, [ the rock.] and on this rock I will build my church, and the gates of hell will not prevail against it."
Remind them that you are following the Church of Christ as handed down through His apostles, not the church of some reformer who came 1500 years later. Besides, you have Luther, Calvin, Zwingli and many other reformers, no two agreed with each other, so which of them is one supposed to follow? Johnny come latelys to Christianity to not have Apostolic Authenticity. These reformers only give their personal interpretation.
Just my 2 cents worth.