Hi there

you said 'are we prepared to live by his principles only or must we continue to rely on the old covenant as well as the new.

Hmmm.
The 'old covenant' is the Ten Commandments, short form of the commandments is the two great commandments.
Yahshua says, 'man shall not live by bread alone, but by every word that proceeds from the mouth of God.'

YHVH Himself spoke these very commandments from his own mouth.
Therefore we are according to the word of Yahshua to live by them.
Only in Christianity do you have this weird concept of replacement.
Remember that Yahshua said, He did not come to abolish the law. He came to make it abound. (to fulfill).
Only through Paul do you get the deceptive notion that the Law ended at the cross.
So wherein does anyone have a problem with 'You shall love YHVH with all your heart, soul, mind and strength and your neighbor as yourself.' Which is, quite frankly, the 'old covenant.'

Michael