Adam Clarke on Hebrews 8:7

If that first had been faultless - This is nearly the same argument with that in Heb 7:11. The simple meaning is: If the first covenant had made a provision for and actually conferred pardon and purity, and given a title to eternal life, then there could have been no need for a second; but the first covenant did not give these things, therefore a second was necessary; and the covenant that gives these things is the Christian covenant.