Yes, the teaching is ethically sound, and quite challenging, because it challenges people's normal and nastier character flaws such as selfishness and vengefulness and suggests a more loving approach to life.

There's definitely some good stuff in there to consider, if one is willing to.

To "lay up treasures in heaven" refers to having treasures of consciousness...as opposed to having material treasures. You can have all the material treasures imaginable and still be miserable, fearful, depressed, angry, vengeful, etc...in other words, you're rich in the world's terms...but you're still unhappy.

But if you are truly happy, in love with life and others and yourself, and at peace within...then you have treasures of consciousness. And that appears to be what Jesus was aiming at in his teachings. They were all about improving one's own consciousness...which then leads to improved behavior in regards to self, life, and others. This is the main point in all the great spiritual teachings and traditions. They are primarily about improving consciousness, since the quality of one's own consciousness is the key to living a positive and useful and happy life.

We were talking about money, weren't we? :) Well, money is just a unit of exchange, and that's a very useful thing to have...it's just that the power of creating it should have been reserved ONLY for governments (who create debt-free money), rather than placed (mostly) in the hands of the privately-owned banks, who are creating ever-increasing amounts of debt-based money out of thin air by lending to governments and the private sector, and thereby making themselves very rich by perpetrating a vast pyramid scheme on all modern societies with their debt-based money. That's why your dollars or your pounds buy less and less real stuff per unit of currency as the years go by. The banks have what amounts to their own "money tree" or digital printing press. They are able to create infinite amounts of new money (plus the interest owed on it!) at will and hold societies hostage through debt, and that should never have been allowed to happen.