Not at all.
When we have two wills and testaments, you always go to the most recent one because there are better promises. Why? Because there has been a change. Usually a New will and Testament has more things, more promises.
The TaNaKh said there would be a New Testament:
ESV Jer. 31:31 “Behold, the days are coming, declares the Lord, when I will make
a new covenant with the house of Israel and the house of Judah,
The author of Hebrews, who understood the Jewish TaNaKh explained it:
Hebrews 8:6 But now hath he obtained a more excellent ministry, by how much also he is the mediator of a
better covenant, which was established upon better promises.
So, when we have a Testament... a covenant... we have to search the terms of the covenant. If you know the legal particulars, you receive the promises of that covenant.
In the TaNaKh it was a series of memorizing the law to fulfill the law to have an open relationship with YHWH. If you didn't, there were consequences. A series of offerings, most with the shedding of blood, had to be fulfilled to get back to relationship.
In the New Covenant, it starts with a fulfilled relationship (as close as a husband and wife). You are already in the open (nothing hidden) relationship and He helps you live your life. If you miss it, love already covered your sins because holy blood was already shed and you move forward with full relationship.
What to do is written in your heart.
The Last Will and Testament (NT) erased some particulars of the First Will and Testament (such as the sacrificial laws), kept some particulars of the First Will and Testament (like worship), and created new particulars in the Last Will and Testament - such as a continual forgiveness because of love.
But if you don't know the terms, then someone will rob your blessings.
So, to go back or to enact the First will and Testament when it is already been replaced (as you seem to suggest), it is to go back to a lesser blessing. You can do it if you want, but it will never match the New Will and Testament.