And this is the substance of the new covenant:
I will put My laws in their mind and write them on their hearts.... " Heb 8:10
Yes, absolutly. This is the nature of the new covenant.
Now what do you suppose those laws would be and where do you think we might find details of them?
Well, let's think about this for a moment. The New Covenant is the law of God that will be written on our hearts and in our minds:
"For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts: and I will be to them a God, and they shall be to me a people: "
(Hebrews 8:10)
And this new covenant replaced the first one:
"In that he saith, A new covenant, he hath made the first old. Now that which decayeth and waxeth old is ready to vanish away."
(Hebrews 8:13)
What then are the laws that he will write on our heart and mind? Is it the laws that he gave to Israel in the old testiment?
We are told in the laws of the first covenant that we are to exact an eye for an eye and a tooth for a tooth:
"Eye for eye, tooth for tooth, hand for hand, foot for foot, Burning for burning, wound for wound, stripe for stripe."
(Exodus 21:24-25)
But Jesus preaches against this in his sermon on the mount:
"Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth: But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also. And if any man will sue thee at the law, and take away thy coat, let him have thy cloke also."
(Matthew 5:38-40)
It seems kind of odd for Jesus to be shunning the very laws he has come to write on our hearts, doesn't it? Why might Jesus in the sermon on the mount have rejected the laws of the first covenant and in their place gave new instructions?
A hint can be found at the top of Hebrews 10:
"For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect."
(Hebrews 10:1)
The law of the old testiment is only a shadow of the true law that Christ came to give. It was this new law that Christ delivered in the sermon on the mount and throughout his ministry. It is the new law that Christ has written on our hearts.
And besides that, I have yet to see a single verse that says that tatoos are a sin. The only one that has been provided here was referenceing marking one's self for the dead. Even if this was referenceing tatoos (which the Hebrew shows it does not) they are tatoos used in a pagan ritual for remembering the dead. I don't now anyone that gets them for that purpose.