Hebrews 8:1-7 (ESV)
Now the point in what we are saying is this: we have such a high priest, one who is seated at the right hand of the throne of the Majesty in heaven,  a minister in the holy places, in the true tent that the Lord set up, not man.  For every high priest is appointed to offer gifts and sacrifices; thus it is necessary for this priest also to have something to offer.  Now if he were on earth, he would not be a priest at all, since there are priests who offer gifts according to the law.  They serve a copy and shadow of the heavenly things. For when Moses was about to erect the tent, he was instructed by God, saying, "See that you make everything according to the pattern that was shown you on the mountain."  But as it is, Christ has obtained a ministry that is as much more excellent than the old as the covenant he mediates is better, since it is enacted on better promises.  For if that first covenant had been faultless, there would have been no occasion to look for a second.
“For if the first covenant had been faultless there would have been no occasion to look for a second.” I still hold my grudge with this bit about covenants. The old “covenant” has been replaced by a Testament, which is a type of covenant, but a very special case. Diatheke, the Greek, is better translated testament. In any case, the author to Hebrews here criticizes the old law. Perhaps you have run into them, the various sects, that try to hedge their bet on Christ by adhering to old testament practices, and often quite selectively. Jehova Witnesses, and Seventh Day Adventists, as well as Mormons to some degree, all do this. It is like betting on black and red at the same time, and expecting a return. But by betting on the law, you show that you don’t believe in Christ, you don’t trust him. The law becomes your idol, your false god. You actually break God’s law, by trying to follow it. This is the fault in the law. It offers what it cannot give.
Now if you don’t like lobster, or mowing the lawn on Saturday, that is your business, but the law forbidding you from eating lobster, or mowing the lawn on Saturday has been abolished. It has been replaced by the New Testament, sealed with the divine blood of Jesus Christ. And for those of you who worship on Sunday, and then make up rules about observing the Sabbath, which you keep on Sunday, well get bent you hypocrites. If you are going to observe the Sabbath, observe it on the Sabbath. Sunday is not the Sabbath. You are breaking the Sabbath, by worshiping on Sunday. What a conundrum for you. But being as Christ rose from the dead, conquering death, and showing that he has fulfilled the law on our behalf, on Sunday, I think I will celebrate that even on Sunday, and take that time to worship God. And not hedging my bet, I will mow the lawn on Saturday if it so moves me to do so. Can’t promise that. Sometimes I mow it on Tuesday. Rarely on Sunday though, as I have better things to do on that day, like relaxing with my wife.