Deuteronomy 4:36
Out of heaven he made thee to hear his voice, that he might instruct thee: and upon earth he shewed thee his great fire; and thou heardest his words out of the midst of the fire. Out of heaven he made thee to hear his voice, that he might instruct thee: and upon earth he shewed thee his great fire; and thou heardest his words out of the midst of the fire.
Out of heaven God caused Israel to hear His voice at Sinai in order to instruct them, and upon earth He showed them His great fire, speaking His words to them from the midst of the fire as He gave them His law. That heavenly voice spoke out of the pillar of cloud, instructing the people in what they should do and what they should not do. The experience was part of God's unique self-revelation and deliverance of Israel, teaching that the Lord alone is God in heaven above and on earth beneath and there is none else.
The words and directions so given are sacred truth expressing the mind of the infinite God, and they must not be altered. Every word is to be cherished, and their specifications never lose their force. The verse belongs to a whole chapter to be studied carefully as Scripture on the sacredness of God's law, given as instruction and charge both to Israel and to God's covenant-keeping people today. That chapter calls for keeping God's statutes and commandments and observing the law proclaimed at Mount Sinai, with the promise that obedience brings blessing, well-being and prolonged days on the earth God gives, for the people and their children.
The warning of the chapter was verified when Israel disobeyed and only two of the adults who left Egypt entered Canaan while the rest died in the wilderness, showing that God vindicates His word when His people depart from His commandments. Observing that law includes keeping the true Sabbath. Faithfulness to the Sabbath means refusing a Sunday law that would close the way to its observance.
The principles of the law are to be acted out in all religious service toward God and toward one another by being Christian gentlemen, loving as brethren, doing no injustice, and always showing liberality, tenderness, compassion and true courtesy. This requires a humbled spirit and a changed heart, the truth is to be preached and not treated as nothing, God is not to be trifled with, He is to be represented through correct principles in everything, and all who depart from His word in action misrepresent His character. The chapter sets forth practical service for God to be walked in as light shining in strong, steady rays across the pathway, combining faith with works rather than merely theoretical belief, including educating students to do service for the Lord. Neglect and unwillingness to do that work fails to set a right example, while God's Spirit and favor are given to those who do it.