I can be found in a Bee Gees refrain
and in a baccarat deck.
Bavarian beer and in any old sayin',
arabs, Oman and Iraq.
I start the name of an old Saudi king,
inside of his kingdom I'm twice.
I am involved when a hen does its thing,
or when you have been told the price.
When you need God, you can use me at will,
children light matches in awe.
I'm there when you're lost, when you neuter or kill,
assert that your word is the law.
What am I?
Looking for a single consonant.
The king ruled until recently.
Iraq works as a clue on the fourth line, but Iran would not. Neither would Qatar.
Hint 4 and 5:
Looking for a non-English letter.