I think most Christians reconcile the three-in-one idea of god like water. Water can have three forms, water, ice, and vapor, and yet all 3 are the same thing. I dont believe the bible would support the Idea of the Trinity, because not sinning does not make you god, since Adam and eve would then have been gods if they hadnt sinned.
Christians, however, are very choosy in what parts of the bible they like to see as significant and those parts which no longer apply. 1st commandment applies, but now we have a 3-in-one God. Though, in english the 1st commandment literally states to put God first, but worshipping other god's like Baal come second.