You've deducted then, from this, that the mark on the wrist is for unbeliever?
3Now the glory of the God of Israel went up from above the cherubim, where it had been, and moved to the threshold of the temple. Then the LORD called to the man clothed in linen who had the writing kit at his side 4and said to him, "Go throughout the city of Jerusalem and put a mark on the foreheads of those who grieve and lament over all the detestable things that are done in it."5
As I listened, he said to the others, "Follow him through the city and kill, without showing pity or compassion.