Deborahmichelle:We are commanded in the Second Commandment not to take the L-rd's name in vain. That is why observant Jews never write out His name in full.
I've always admired the reverence with which Jewish believers hold the Lord's name. I read somewhere that ancient scribes, once they wrote the Lord's name in Scripture, would put away the pen/stylus/writing instrument and never use it again, because they believed that nothing was good enough to follow the writing of the Lord's name.
Deb, I always thought that was the reason my Jewish friends never wrote out God's name in full, so thank you for teaching me something new! 
