sign of the Abrahamic covenant: physical circumcision
sign of the Mosaic covenant: physical sabbath inactivity
sign of the new covenant: physical baptism ((tho some will argue the Lord's supper))
in no case does the sign supplant the reality.
Colossians 2:11, Romans 2:25-29, 1 Corinthians 7:19 & the witness of the epistle to the Galatians show that physical circumcision is nothing more than a sign and cannot avail, even can become sin if one is basing their salvation on completion of the rite.
the witness of the confrontations of the pharisees with Christ throughout the gospels, as well as the explicit commands in Romans 14 & Colossians 2 show physical sabbath observation is nothing more than a sign and avails nothing. likewise with the witness of Galatians, sabbath-observation in the flesh can be sin, a mockery of Christ, if one bases their salvation on its ceremonial keeping.
in the same way water baptism avails nothing in and of itself: Matthew 3:11, Luke 3:16, Mark 1:8, Acts 1:5, Acts 11:16 all testify of this -- for the baptism that is effective is the one that actually places us in Christ, just as 1 Corinthians 10:2 tells us all Israel was baptized into Moses, yet not all Israel is saved nor is even all Israel, "Israel" -- in fact 1 Corinthians 10:2 shows us a pattern, saying that they were baptized through the cloud and sea, demonstrating that it is a sign, that the reality is not merely carnally carrying out a right, but spiritual -- as God testifies, His word is Spirit: the flesh profits nothing ((John 6:63)) and His apostle testifies, it is the Spirit that seals us, not ritual ceremony, not H2O, not cutting of the flesh.
even if we admit the Lord's supper is the sign of the covenant in Christ's blood, then it remains merely symbolic, unable to avail. for Paul tells us we may drink judgement by taking it ((1 Corinthians 11:29, c.f.e. Proverbs 26:6)) and our Lord God Himself informs us in its instantiation the wine is His blood, the bread His flesh: clearly a symbol, not the reality.
the reality is Christ, oh friends: it is all about Christ, always
God calls sabbath a symbol Himself: Exodus 31:13, Ezekiel 20:12. in two witnesses He explicitly tells us their purpose: that Israel should know it is God who sanctifies. this is a tacit rebuke to the idea that anyone sanctifies themselves; it is by inactivity that sabbath was observed under Moses; by ceasing from one's own work ((c.f.e. Hebrews 4:10 - "whoever enters God's rest")) -- how then can specifically "nothing-doing" on certain days profit for anything? it is a remembrance and shadow, pointing at Christ's doing what neither our doing or non-doing can possibly accomplish.
in yet a third witness by the mouth of God, Hebrews 4 tells us unquestionably that ceremonial sabbath observance in the flesh is a symbolic action - as Colossians 2 again explicitly tells us for yet a 4th witness to those hard of heart and dull of hearing. for Hebrews 4 describes David saying "today" in like manner as the sabbath, and describes the Hebrews in their wandering not entering Canaan as failing to enter rest, and describes even Joshua leading them into the land, physically, as not being entering the true rest.
we must ask ourselves if we are preaching Christ or preaching ritual ceremony.
the Jews scrupulously kept ceremony, but it profited nothing.
what do you meditate on, during sabbath ((friday sundown to saturday sundown))?
do you think about how much better you are than those people who do any physical activity that day?
do you think about how you are blessed because you went to church then instead of sunday, and curse those servants who don't do as you do?
do you imagine that your obedience to the law, which cannot produce righteousness ((Galatians 2:21)), is producing righteousness?
do you thank God that He has taken away that which condemns us?
do you bless the Lord for the promise which is by faith?
do you extol Him for His great mercy and love towards us?
do you plot how to make another sabbath thread & finally "get" all those pesky Christians who won't allow you to judge them?
do you think about Jesus or about yourself? about His works or yours?
do you think about loving others or plot how to persecute and condemn them?
there is no rest, saith my God, for the wicked.