The Jew already had every NT blessing under the eternal Sinai covenant

From the perspective of the Torah itself, this is a very important question. If an Israelite stood at Mount Sinai, heard God's voice, and entered into the covenant that God made with Israel, then what did that person already possess? The answer is: according to the Hebrew Scriptures, he already possessed everything necessary for a covenant relationship with God.

Here are the major covenant blessings that Israel already had.

God had already chosen them.

Before the Law was even given, God declared:

"You shall be My treasured possession... a kingdom of priests and a holy nation." (Exodus 19:5–6)

Israel did not become God's people because of a future Messiah. They already were His covenant people.

God's Law was already in their hearts.

Many Christians say the New Testament introduced the Law being written on the heart. Yet Moses says:

"This commandment... is very near you. It is in your mouth and in your heart, so that you may do it." (Deuteronomy 30:11–14)

Paul quotes this passage in Romans 10, but in its original context Moses is speaking about the Torah itself. God says the commandments are not impossible—they are near, in the heart, so they can be obeyed.

Forgiveness was already available.

The Torah never teaches that every sin required an animal sacrifice.

Many sins were forgiven simply through repentance, confession, restitution where necessary, and God's mercy.

For example:

Leviticus 5 includes confession.

Numbers 5 requires confession and repayment.

Deuteronomy repeatedly calls Israel to return to God.

Solomon later prayed that if Israel repented, God would forgive them (1 Kings 8).

Even David, after his sin with Bathsheba, wrote:

"The sacrifices of God are a broken spirit..." (Psalm 51)

God forgave him, although no sacrifice existed in the Torah for adultery and murder.

They already had the Holy Spirit.

God's Spirit came upon Moses, the seventy elders, Joshua, the judges, David, and many prophets.

The Spirit was not unknown before the New Testament.

They already had direct access to God through prayer.

Throughout the Tanakh people prayed directly to God and were heard.

Abraham, Moses, Hannah, Samuel, David, Elijah, Hezekiah, Daniel, Ezra, and Nehemiah all approached God without another mediator.

They already had eternal life as their hope.

The New Testament often presents eternal life as something new, yet the Hebrew Scriptures already speak of everlasting life.

Daniel 12:2 says:

"Many who sleep in the dust of the earth shall awake, some to everlasting life..."

Psalm 16 and Psalm 73 also express hope beyond death.

They were already in an everlasting covenant.

God repeatedly calls His covenant with Israel everlasting.

Exodus 31:16–17

Leviticus 24:8

Deuteronomy 29

Isaiah 55:3

Jeremiah 32:40

If God calls His covenant everlasting, it cannot simply expire.

So what does the New Testament claim to add?

Christians generally answer:

complete forgiveness through Jesus,

the indwelling Holy Spirit for all believers,

a new covenant replacing or fulfilling the Sinai covenant.

However, from the perspective of the Tanakh, many of these blessings were already realities:

Israel was already God's people.

The Torah was already in their hearts.

Repentance already brought forgiveness.

The Holy Spirit was already active.

Prayer already reached God.

Eternal life was already promised.

God's covenant was already described as everlasting.

That is why your question is significant. If every essential covenant blessing was already available under the covenant God Himself established at Sinai, then the central theological question becomes: What genuinely new covenant blessing was lacking that required replacing or superseding an everlasting covenant? That question lies at the heart of the long-standing debate between traditional Judaism and Christian interpretations of the New Testament.