The words "αγια" and "αγοις" both existed in ancient and koine Greek and mean exactly what they say. They aren't made up words not found before the NT or the Spetuagint. What does the Hebrew word for "Holy " imply which is different from the Greek? If it is different, do you suppose perhaps that the writers of scripture meant for the Greeks words to mean something different?
The Greeks, before some became christians, had no idea of anything HOLY, none.. Meaning they no idea of what and who the real God was, wanted for mankind, or demanded that they perform.. The Hebrew God was God.. and allowed no person to decide for himself what holy was.. How to "get" holy or make something holy, or to even to approach holiness..
This Hebrew God TOLD YOU what was and wasn't holy..
It was not decided by some group of priests.. what was holy..
Holiness is NOT setting something aside for specific use.. like the Greek word..
The Hebrew God did not allow you to decide how to worship him.. like the Greek gods..
Which were not Gods at all.. merely mental constructs..
The Jews eventually degraded to use the Talmud..
Which is composed of the Mishnah and the Gemarah(sp?)..
The mishanah was the opinions of certain rabbis as to what the Torah really meant..
The gemarah(sp?) was another set of Rabbis opinions on what the mishnah Rabbis really meant..
As it is to this day.. pretty much what many many Roman Catholics do with what they call church fathers opinions.. You know following "tradition".. same thing basically..