Introduction:
The Fourth Commandment is a pivotal element of the Decalogue, commonly known as the Ten Commandments, which were given by God to Moses on Mount Sinai. This commandment emphasizes the importance of the Sabbath day, setting it apart as a day of rest and worship. It is found in both Exodus 20:8-11 and Deuteronomy 5:12-15, with slight variations in wording but consistent in its core message.

Biblical Text:
In Exodus 20:8-11 , the Fourth Commandment is stated as follows:
"Remember the Sabbath day by keeping it holy. Six days you shall labor and do all your work, but the seventh day is a Sabbath to the LORD your God, on which you must not do any work—neither you, nor your son or daughter, nor your manservant or maidservant, nor your livestock, nor the foreigner within your gates. For in six days the LORD made the heavens and the earth and the sea and all that is in them, but on the seventh day He rested. Therefore the LORD blessed the Sabbath day and set it apart as holy."

In Deuteronomy 5:12-15 , it is reiterated with an additional emphasis on remembrance:
"Remember the Sabbath day by keeping it holy, as the LORD your God has commanded you. Six days you shall labor and do all your work, but the seventh day is a Sabbath to the LORD your God, on which you must not do any work—neither you, nor your son or daughter, nor your manservant or maidservant, nor your ox or donkey or any of your livestock, nor the foreigner within your gates, so that your manservant and maidservant may rest as you do. Remember that you were a slave in the land of Egypt, and the LORD your God brought you out of there with a mighty hand and an outstretched arm. Therefore the LORD your God has commanded you to observe the Sabbath day."

Theological Significance:
The Fourth Commandment serves as a reminder of God's creation and His deliverance of Israel from Egypt. It underscores the rhythm of work and rest established by God Himself. The commandment is not merely a legalistic requirement but a gift, offering rest and spiritual renewal. It reflects God's care for humanity, ensuring that all, including servants and animals, receive rest.

Sabbath Observance:
The observance of the Sabbath has been a subject of theological discussion and practice throughout history. Traditionally, the Sabbath is observed from Friday evening to Saturday evening, in accordance with Jewish custom. However, many Christians observe Sunday, the first day of the week, as the Lord's Day, commemorating the resurrection of Jesus Christ. This shift is rooted in the early church's practice and is seen as a fulfillment of the Sabbath principle in the new covenant.

Moral and Ethical Implications:
The Fourth Commandment calls for a balance between labor and rest, emphasizing the sanctity of time dedicated to God. It challenges individuals to prioritize spiritual matters over material pursuits and to trust in God's provision. The commandment also promotes social justice by ensuring that all members of society, regardless of status, have the opportunity for rest and worship.

Contemporary Application:
In today's fast-paced world, the principle of Sabbath rest remains relevant. It invites believers to pause, reflect, and realign their lives with God's purposes. Observing a day of rest fosters community, family bonds, and personal well-being. It serves as a countercultural statement against the relentless demands of modern life, affirming the value of rest and worship in the believer's life.

Conclusion:
The Fourth Commandment continues to be a vital aspect of Christian ethics and spirituality. It calls believers to remember God's creative and redemptive acts, to rest in His provision, and to honor Him through dedicated time for worship and reflection.