How old is the Irish language?

How old is the Irish (Gaelic) language? Why am I asking this? Because there is something very interesting in the Irish language, which can possibly help us determine when and where this language had originally developed...This:

This image shows a person standing at the door of his house. The door is facing east. What is astounding is how these words for direction of movement and orientation match in the Irish (Gaelic) language...

This language characteristic can only be explained if we assume that this part of the Irish language was developed by the culture which lived in a world which faced east...Where facing east was something everyone did every day...

Like if their houses were built in such a way that the house entrances faced east...

It turns out that most rectangular [Irish] Neolithic houses had east facing entrances...

The same goes for the Irish Bronze Age round houses, which were also predominantly built with their doors facing East or South East...

So if you were a person living in this kind of the world, then your language will naturally develop in such a way that North is Leftward, South is Rightward...

I can't see any other reason why such a strange cultural trait would develop...Can you?

So when did this part of the Irish language develop? 

During Neolithic, 4th - 3rd millennium BC?

During Bronze Age, 3rd - 1st millennium BC?

Irish dictionaries

S. Dineen 1904 dictionary

Ó Dónaill 1977 dictionary

Neolithic houses

"Landscapes of Neolithic Ireland" by Gabriel Cooney

Bronze Age houses

"Bronze Age settlement in Oranmore" - blog article

"Middle Bronze Age Houses At Mitchelstown, Co. Cork" - excavation report

PS: The only other culture where I found something similar is Hebrew culture...

In "Doorway Orientation, Settlement Planning and Cosmology in Ancient Israel During Iron Age II" by Avraham Faust we can read that:

"An examination of Iron Age buildings and settlements in ancient Israel indicates that a large number of them were oriented toward the east, while the west was extremely under-represented...

An examination of various climatic and functional considerations does not seem to explain the phenomenon. But ethnographic studies, show that cosmological principles can have on the planning of buildings and settlements, and that in many cases the east is preferred...

The common Biblical Hebrew word for east is qedma (forward), while the west is ahora (backward). Additional words for these directions indicate that the east had a good connotation while the west had a bad one...

Thus, the archaeological pattern, along with language and texts (which are used as a substitute for human informants), seem to give an important insight into some of the cosmological principles of the ancient Israelites"...

I want to thank @ainiladra for pointing me to this table found in "Handbook of Ugaritic Studies" by Wilfred Watson and Nicolas Wyatt, which shows that exactly the same overlap between the sides of the world and directions found in Gaelic, is also found in Ugaritic, Akkadian, Hebrew and Arabic...And it obviously dates to at least the Bronze Age... 

Sekirica

The (most likely ceremonial) battle axe "sagaris" of the Scythian period, 7th century BC. The Hermitage Museum, Saint Petersburg (Russia)....

The sagaris (Ancient Greek: Σάγαρις) is an ancient Iranian shafted weapon used by the horse-riding ancient Saka and Scythian peoples of the great Eurasian steppe. It was used also by Western and Central Asian peoples: the Medes, Persians, Parthians, Indo-Saka, Kushans, Mossynoeci, and others living within the milieu of Iranian peoples. According to Aristarchus of Samothrace, the legendary Amazons used the sagaris, as well. In The Histories, Herodotus attributes the sagaris to the Sacae Scythians in the army-list of Xerxes the Great...

The word "σάγαρις" is apparently a "...foreign word without known etymology...but one would rather...expect Iranian origin, and it is probably a cognate to Latin secūris (broad axe) and Proto-Slavic *sekyra (broad axe)..."

Hmmm....

Slavic word for an axe is sekira (sikira). While sekirica (pronounced sekiritsa), sikirica (pronounced sikiritsa) means "little axe", from sekira (axe) with "ica" diminutive ending which put together means "small (head) axe"...

Sounds very much like "sagaris" right? Which was a small head axe on a long handle...Like Scythian battle axe...Is there any etymology for σάγαρις (sagaris) in Iranian languages I wonder...If not, is it possible that σάγαρις (sagaris) came into Ancient Greek via an intermediate (Proto) Slavic???

Anyway, It gets more interesting...Enter the Akkadians...

In Ancient Greek, the word for an axe was πέλεκυς (pelekus) and for axe handle was πέλεκκον (pélekkon)...Apparently:

"... πέλεκυς is often considered a Wanderwort (A loanword that has spread to many different languages, often through trade or the adoption of foreign cultural practices), because of the similarity to Arabic فَلَقَ‎ (falaqa) meaning to split apart which comes from Akkadian 𒁄 (pilakku, pilaqqu) meaning wooden handle; spindle, harp, which itself comes from Sumerian 𒁄 (balag) meaning wooden handle; spindle, harp; possibly a split piece of wood or wooden wedge..."

A Wanderwort you say...Well if πέλεκυς is a Wanderwort, why is σάγαρις not one too? Because

Bronze axe head, Akkadian, c. 2340-2200 BC, inscribed with owner's name. Akkadian 𒅆𒆕 "šukurru" (metal wedge, spear, axe)...Officially "not related" to Slavic sekira (axe), Latin secūris (axe) and Ancient Greek σάγαρις "ságaris", Scythian axe. 

Definitely is related...

One of the Akkadian words for "destiny" is "isqu" meaning "lot" which derives from "esēqu" (to make a drawing, to incise a relief) and specifically "to apportion lots"...Etymology of the Akkadian word from: "Luck, Fortune, and Destiny in Ancient Mesopotamia Or How the Sumerians and Babylonians Thought of Their Place in the Flow of Things"...

Which is very interesting, considering that in Slavic languages "sek" (From PIE "sek" meaning to cut) means "to cut",  and "isek" means "to to cut out, to apportion".

How are these words not related? When it comes to Ancient Greek πέλεκυς (pelekus), apparently "...some suggest that the Proto-Indo-European terms are ultimately borrowed from...Akkadian..." Is it possible that  Akkadian words with "sk" root were borrowed into Akkadian from som IE language? Considering that the "sk" root only exists in IE languages...

And interestingly, we again find link between Slavic and Akkadian...I talked about few more in my posts "Kurban", "Pelasgos", "Kaunakes", "Zib-Ba-An-Na"...

Strange...Slavic being "the youngest IE language branch" and all that...