Not sure what is meant by "the old Russian". An old Russian person would call God the same as a young Russian would. If the question is about the old Russian language (the Old Church Slavonic), the word for God is one of the few that have not changed in modern Russian.
Regardless, the answer is bog.
If addressing God in a plea, as in God save Russia, then it's bozhe.
Finally, a Russian may refer to God as Lord, in which case it becomes gospot.
Russian Orthodox is a Orthodox branch of Christianity they would call god God the same as any other Christians in the world
"God of Death" in Russian would be Bog Smerti.
"Without god" in Russian is без бога, pronounced bez boga
Dazhbogm (also Dadzbog), the Russian god of the sun, son of the sky god Svarog, and brother to fire god Svarozhich.
собака is what you call a dog in russian. why did you want know anyway?
Russian for "go with God" is ступай с Богом. It is pronounced stupai s bogom.
Svarog
milk+vodka=white russian....
You can write "Бог благословит тебя" in Russian, which translates to "God bless you."
The Russian money is called the rouble.
What do you call a Russian animal that gives milk...A Moscow. What do you do to watch a Russian hockey team from afar...Ukraine your neck. What do you call a cross between a Russian and an Irishman...Sam O'var.
Firearm + Vodka = Russian Roulette