I say Alpha and Omega from our perspective in the New Covenant.
Taw “tau” is God’s symbol, meaning the same thing. Eternal Truth, I AM who AM., Uncreated Eternal, Ever Present, Omnipresent.
wayyōmɛr YHWH ʾēlå̄w ʿăḇōr bəṯōḵ hå̄ʿīr bəṯōḵ yərūšå̄lå̄yim
wəhiṯwīṯå̄ tå̄w ʿal-miṣḥōṯ hå̄ʾănå̄šīm hannɛʾɛ̆nå̄ḥīm wəhannɛʾɛ̆nå̄qīm ʿal kål-hattōʿēḇōṯ hannaʿăśōṯ bəṯōḵå̄h
Ezekiel 9:4
“And the Lord said to him: Go through the midst of the city, through the midst of Jerusalem: and mark Thau upon the foreheads of the men that sigh, and mourn for all the abominations that are committed in the midst thereof.
5 And to the others he said in my hearing: Go ye after him through the city, and strike: let not your eyes spare, nor be ye moved with pity.
6 Utterly destroy old and young, maidens, children and women: but upon whomsoever you shall see Thau, kill him not, and begin ye at my sanctuary. So they began at the ancient men who were before the house.”
Taw is God’s symbol and Seal on the foreheads of his own.
Satan and the Antichrist mock this Seal of God by marking the foreheads of his own with blasphemy against God.
This is why the Seal of God Tau is publicaly displayed on the forehead as witness before men.
Just as there was no mercy in Ezekiel, there will be no mercy for those marked with the mark of the beast, as opposed to those marked with God’s Seal Taw.
Something cool and beautiful Psalm 139
7 Where can I go from your Spirit?
Where can I flee from your presence?
8 If I go up to the heavens, you are there;
if I make my bed in the depths, you are there.
9 If I rise on the wings of the dawn, ( East )
if I settle on the far side of the sea, ( West )
10 even there your hand will guide me,
your right hand will hold me fast.
11 If I say, “Surely the darkness will hide me
and the light become night around me,”
12 even the darkness will not be dark to you;
the night will shine like the day,
for darkness is as light to you.
It was explained to me by a Rabbi who converted to Christianity that in Sacerdotal Judaism the Israelites Crossed themselves at the reading of this part of the Psalm.
If I go up to the heavens, you are there;
if I make my bed in the depths, you are there.
If I rise on the wings of the dawn, ( East )
if I settle on the far side of the sea, ( West )
This is the sign of God but it also shows the Omnipresent and Eternal Nature of God, Eternal Truth. The Israelites inculcated spiritual realities into physical representations in worship, and many other ways, customs etc. Even culinary things and dress.
A whole lot more can be said on it, the Old Testament has many other references denoting the cross or Tau.