Walt said:
Maybe I read Acts 10 wrong, but I think that what the blood of Messiah made clean was people, specifically Cornelius and his household.
Indeed. You've made my point. Cornelius was a gentile and brought with him all the gentile 'baggage' of customs foreign to the Hebrews and contrary to the customs imposed upon them by God when He led them Himself. Yet, God gave Peter a vision regarding a violation of these Hebrew customs and when Peter responded by declaring he would not violate God's law (in Peter's limited understanding thereof), God admonished him with the words "Do not call anything impure that God has made clean." A key chapter to read in this case is Romans 14, for it clarifies this greatly and instructs us regarding how the weaker and stronger among us are to treat one-another when such controversies arise.
http://www.biblegateway.com/passage/?search=Romans 14&version=ESV
In any case, when the Lord convicted, quickened, and finally called me, I already had four tattoos; one of which was quite offensive to particular people who might see it. I chose to cover that mistake with a copy of a famous medieval christian painting to avoid such offense. My conviction remains the most intense emotional and personal event of my life. His spirit spoke directly through my utter depravity, used my own pride to do so, and utterly destroyed my protest against His rule over my life through a miracle involving the text of the verse Proverbs 3:5. Thus, I chose to tattoo the text of Proverbs 3:5 on the back of my neck to honor His work, and I love to tell the story to others. Later, I choose to tattoo "It is finished" (John 19:30) on my outer right forearm, and "He has risen" (Mark 16:6) on my outer left forearm; and I'm very happy to tell people that notice them why I would do such a thing. Finally, when He answered my prayer for children, I chose to have an arrow tattooed on my calf for each child he gives me to remind me of who builds the house and how very great a blessing it is to be the head thereof under His rule (Psalm 127 - I hope my calf might one day look as a quiver full of arrows). This provides yet another opportunity to share His word.
When I married the lovely bride He gave me, I choose to have our wedding rings inscribed in Hebrew. Mine is inscribed "as for me and my house, we will serve the Lord" (Joshua 24:15) and I've been playing with the idea of having that tattooed on my ring finger. I'm sure that if I do, someone will notice and ask what it says and why I chose to do it; which would provide yet more opportunity for "good works prepared beforehand, that we should walk in them" (Ephesians 2:10). When my two-year-old son wants to help us with a task it usually takes much longer to accomplish and there is more mess to clean up. We do not let him participate because we need his help, but rather because he wants to help. Whereas God is a much better father than any of us can ever hope to be, I have every confidence that God bears with great patience all my futile and misguided attempts to serve Him and cleans up the extra mess I leave when I think I've finished.
Perhaps our Lord chose to call me because I'm honored and delighted to bear His Word on the flesh He gave me; to make known to everyone who sees me that it is He who I worship and serve. Perhaps He needed a gentile with no 'baggage' regarding tattoos to do this particular work among others not yet called. He calls many of us at various times in our lives, and from many places and traditions that are not for the pious. Perhaps I'm misguided. Regardless, I know He called me and He gave me Jesus. Thus, glory to God that my good works are not my own, and praise be to God that my errors will not be counted against me.
In any case, as I said before, I do not wish to encourage anyone to get tattoos. Nor is it my plan to convince anyone of what our Lord thinks on the matter. All I seek to do is point out that (1) God invited gentiles (with their tattoos and other foreign customs) into His family after our Lord and Savior, Christ, 'finished it' for all eternity; and (2) that He says "so do not let what you regard as good be spoken of as evil" (Romans 14:16); and finally (3) that He says "let not the one who eats despise the one who abstains, and let not the one who abstains pass judgment on the one who eats, for God has welcomed him" (Romans 14:3). Perhaps also noteworthy, I caution against stretching this too far (i.e. rightly divide the ceremonial or specific commands to the Hebrews from sin applicable to all).