Please cite the scripture saying that we are to have ash markings on our forheads, in the shape of a cross. Thanks. By the way, it seems that it may be more of a 'tradition of men', than a request of YHWH. ;)
1 Kings 18:21 (JPS)
21 And Elijah came near unto all the people, and said: 'How long halt ye between two opinions? if YHWH be God, follow Him; but if Baal, follow him.' And the people answered him not a word.
Now a rephrase...
1 Kings 18:21
21 And Elijah came near unto all the people, and said: 'How long halt ye between two opinions? if YHWH be God, follow Him; but if Jesus, follow him.' And the people answered him not a word.
At some point you will have to make a choice