I'm going to go way out on a limb here, but I consider myself a Christian and I don't think Jesus Christ would buy into all this sacrificing and grovelling virtually all the current "Christian" religions would have us believe and practice. But that's just me.

Coveting is a strong word, but failing to recognize beauty is just silly as well as self-defeating. I do tell them, and their husbands. Everyone is happy, because they all trust me implicitly. I use adjectives like "beautiful", gorgeous", and "striking", and avoid one's like "hot". Although I do call one Mexican buddies Greek wife, the "Hot Greek" because she is beautiful and quite a handful (very active in Republican politics ... and everything). We are co celebrating our birthdays this Saturday (not the day but close for both).

It is easy to foresee the limits of self-interest if one's perspective is narrow. For example, killing another is fine for self-interest, until one realizes one will be at minimum ostracized, and one needs and values the contributions and value of others. Ayn directly addresses this (but I don't recall the reference. Maybe that twerp, EWE, can quote it from his idiot homework assignments).

In my "reasonable libertarian" mind (as opposed to radical hard on Libertarians), there is a similar place for government's role. A capitalist system WILL find a monotonic optimum, proven over and over. However, it is limited by local minima. If there is a massive investment required, the investors may not be able to recover their investments within their risk tolerance (or even their lifetimes). In this case, it will converge to a local minima, not a global minima. I argue the interstate highway system overcame such local minima. And yes, I recognize others don't agree, including Milton Friedman, but being in business, no one was going to make that investment, or overcome the local obstructions and build such a system. Maybe Elon would do it now, but we have already benefited from it for 70 years.
Of course there is the issue of shutting down a successful program when it is done, but that is another issue.

To me that is the government inverse, book ending self-interest.

Respectfully, I don't see how Christianity helps. It wants you to sacrifice yourself and your happiness on Earth for the sake of a supernatural promise of eternal life and joy in heaven. The trouble is, we only live once, and the only happiness is that which we can find in reality. The supernatural is so called because no one has ever shown that it exists, and indeed, it could not exist without violating many known laws of nature.

As others have noted, rational self interest means seeking your happiness and survival with a view to the full term of your life and the long term relating to all your goals and values. It is not short-term grasping, it is long-term and thus relies on well-established principles.

study RATIONAL self-interest....

Self interest is always present. Rational self interest is not always present.
From The Objectivist's Ethics.
"A being who does not know automatically what is true or false, cannot know automatically what is right or wrong, what is good for him or evil. Yet he needs that knowledge in order to live. He is not exempt from the laws of reality, he is a specific organism of a specific nature that requires specific actions to sustain his life. He cannot achieve his survival by arbitrary means nor by random motions nor by blind urges nor by chance nor by whim. That which his survival requires is set by his nature and is not open to his choice. What is open to his choice is only whether he will discover it or not, whether he will choose the right goals and values or not. He is free to make the wrong choice, but not free to succeed with it. He is free to evade reality, he is free to unfocus his mind and stumble blindly down any road he pleases, but not free to avoid the abyss he refuses to see. Knowledge, for any conscious organism, is the means of survival; to a living consciousness, every “is” implies an “ought.” Man is free to choose not to be conscious, but not free to escape the penalty of unconsciousness: destruction. Man is the only living species that has the power to act as his own destroyer — and that is the way he has acted through most of his history."

My take is Ayn Rand draws a difference between rational self interest (Virtue of Selfishness) and flat out greed as they are not the same thing, unlike the left that tries to equate the two.

Man—every man—is an end in himself, not a means to the ends of others; he must live for his own sake, neither sacrificing himself to others nor sacrificing others to himself; he must work for his rational self-interest, with the achievement of his own happiness as the highest moral purpose of his life. Ayn Rand

"Rightful liberty is unobstructed action according to our will within limits drawn around us by the equal rights of others. I do not add 'within the limits of the law' because law is often but the tyrant's will, and always so when it violates the rights of the individual." Thomas Jefferson