Why is the Old Testament called eternal?
Most evangelicals say that the Old Testament was meant to be temporary covenant, one that was planned to be replaced by a better covenant, if that’s the case, why is this covenant (or series of them) in the Old testament frequently called an “everlasting covenant” not a “temporary covenant”? In fact, in Psalm 19:7 the Law is called perfect, which leads us to wonder, why should a “perfect” Law need replacing? (See below for examples)
Why does OT eschatalogical prophecy of the future include a restoration of Old Testament Law?
In fact Zechariah has a prophecy regarding the end times (Zech14:4-13) which undeniably shows the “the Day of the Lord.” In this prophecy The Lords feet rest on the Mount of Olives, there is eternal daytime, no night, and God ushers his reign of peace for the whole earth. During this eternal kingdom, God commands all nations to obey Old Testament law and celebrate the feast of Booths (Zech 14:16-19). Likewise, we see temple sacrifices continue in this vision of the future (Zech 14:21).
A few examples of Old Testament edicts described as Eternal/everlasting
“The Israelites are to observe the Sabbath, celebrating it for the generations to come as an ENDURING covenant” (Exod 31:16)
“The secret things belong to Yahweh our God, but the things revealed belong to us and to our children FOREVER, that we may follow all the words of this law” (Deut 29:29)
“A servant who is born in your house or who is bought with your money shall surely be circumcised; thus shall My covenant be in your flesh for an EVERLASTING covenant.” (Gen 17:13)
“God said, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an EVERLASTING covenant for his offspring after him.” (Genesis 17:19)
“The earth is defiled by its people; they have disobeyed the laws, violated the statutes and broken the EVERLASTING covenant.” (Isaiah 24:5)
“it is from the people of Israel as a covenant FOREVER.” (Leviticus 24:8)
“It is an EVERLASTING covenant of salt before the Lord to you and your descendants with you.”(Num 18:19)