No-one would, I hope, suggest that the second commandment was ever only applicable to Jews.
KJV Exodus 20:4-5
4 Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth:
5 Thou shalt not bow down thyself to them, nor serve them: for I the LORD thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me;
After all, in discussions with Catholics do we not all refer to this Commandment to warm them concerning statues and images in their churches and homes? Do we not then affirm the relevancy of the ten commandments to the Christian church? Especially when we start claiming that we are saved by grace, therefore the commandments have no relevance in the plan of redemption, we need to consider the last verse of that commandment...
KJV Exodus 20:6
6 And shewing mercy unto thousands of them that love me, and keep my commandments.