2Co 3:6 ¶ Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.
7 But if the ministration of death, written and engraven in stones, was glorious, so that the children of Israel could not stedfastly behold the face of Moses for the glory of his countenance; which glory was to be done away:
8 How shall not the ministration of the spirit be rather glorious?
9 For if the ministration of condemnation be glory, much more doth the ministration of righteousness exceed in glory.
10 For even that which was made glorious had no glory in this respect, by reason of the glory that excelleth.
11 For if that which is done away was glorious, much more that which remaineth is glorious.
Ministration of DEATH, written and engraved on stones ...only the Ten Commandments was written and engraved on stones. That has passed away and we now serve God. not according to the "letter" but according to the "Spirit"
Those verses do not say that the ten commandments were done away. They say the face of Moses shone with glory and that glory with which Moses face was shining was done away.
Exodus 34:29-35
(29) And it came to pass, when Moses came down from mount Sinai with the two tables of testimony in Moses' hand, when he came down from the mount,
that Moses wist not that the skin of his face shone while he talked with him.
(30) And when Aaron and all the children of Israel saw Moses, behold,
the skin of his face shone; and they were afraid to come nigh him.
(31) And Moses called unto them; and Aaron and all the rulers of the congregation returned unto him: and Moses talked with them.
(32) And afterward all the children of Israel came nigh: and he gave them in commandment all that the LORD had spoken with him in mount Sinai.
(33) And till Moses had done speaking with them,
he put a vail on his face.
(34) But when Moses went in before the LORD to speak with him,
he took the vail off, until he came out. And he came out, and spake unto the children of Israel that which he was commanded.
(35) And the children of Israel saw the face of Moses,
that the skin of Moses' face shone: and Moses put the vail upon his face again, until he went in to speak with him.
These verses show the face of Moses shone with the glory of God after being with God so that Moses had to put a vail on his face when talking to the people. The glory on Moses face did not last for ever, it was done away. What remained after the glory of Moses face was done away? The ten commandments.