The good mark comes from observing the festival of Matzoh See: Shemot 13
The bad mark comes from, well read from the Quran
48. Surah Al-Fath (The Victory)
29. Muhammad () is the Messenger of Allah, and those who are with him are severe against disbelievers, and merciful among themselves. You see them bowing and falling down prostrate (in prayer), seeking Bounty from Allah and (His) Good Pleasure. The mark of them (i.e. of their Faith) is on their faces (foreheads) from the traces of (their) prostration (during prayers). This is their description in the Taurat (Torah). But their description in the Injeel (Gospel) is like a (sown) seed which sends forth its shoot, then makes it strong, it then becomes thick, and it stands straight on its stem, delighting the sowers that He may enrage the disbelievers with them. Allah has promised those among them who believe (i.e. all those who follow Islamic Monotheism, the religion of Prophet Muhammad till the Day of Resurrection) and do righteous good deeds, forgiveness and a mighty reward (i.e. Paradise).
http://www.noblequran.com/translation/
The mark of them (i.e. of their Faith) is on their faces (foreheads) from the traces of (their) prostration (during prayers).
You get the 'bad mark' from bowing to Mecca...
The mark (mint) in the hand is the Jizya tax, you pay with the right hand.
http://www.thereligionofpeace.com/pages/quran/jizya.aspx
I've got the good mark from matzah!
(Ezekiel 9:4) And the LORD said unto him, Go through the midst of the city, through the midst of Jerusalem, and set a mark upon the foreheads of the men that sigh and that cry for all the abominations that be done in the midst thereof.
mark = Strong’s H8420 = tav
How did they write the letter tav in Ezekiel’s day ?
When they marched through the desert for 40 years they were lined up and if you could have watch them from the sky they marched in the sign of the cross
The cross is the sign of the covenant