The Ten Commandments were instituted within the Old Testament of the Holy Bible. These rules and regulations were put in place so it would be known what sin is, and how each person should live for God. With the coming of God in the flesh, and the fulfillment of God's plan these laws were abolished.
These Ten Commandments were introduced at a time when God had selected a people to become his chosen people.
Exodus 20 of the bible lists these Commandments as follows:
Thou shalt have no other gods before me.
Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth: Thou shalt not bow down thyself to them, nor serve them: for I the LORD thy God am a jealous God.
Thou shalt not take the name of the LORD thy God in vain; for the LORD will not hold him guiltless that taketh his name in vain.
Remember the sabbath day, to keep it holy.
Honour thy father and thy mother: that thy days may be long upon the land which the LORD thy God giveth thee.
Thou shalt not kill.
Thou shalt not commit adultery.
Thou shalt not steal.
Thou shalt not bear false witness against thy neighbour.
Thou shalt not covet thy neighbour's house, thou shalt not covet thy neighbour's wife, nor his manservant, nor his maidservant, nor his ox, nor his ass, nor any thing that is thy neighbour's.
The coming of Jesus to earth, and his dying on the cross lead to the law being fulfilled. This also led to an abandonment of the law of commandments.
In the book of Romans chapter seven, the bible speaks of followers of Christ being dead to the law by the body of Christ. They have been delivered from the law, and being dead to the law, should serve in newness of spirit, and not in the oldness of the letter.
Romans chapter seven then goes on further to be specific of some aspects of this law that it refers to, and the 10th commandment was highlighted by the writer as one of those aspects of the law which was important, because it has thought him what sin is.
Having said this, however, these Ten Commandments have been replaced by two chief commandments i.e.
Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind.
Thou shalt love thy neighbour as thyself.
This would properly explain why there is no need to keep the Sabbath day holy. Which is the forth commandment.