Property Rights
Property rights are the backbone of a Just Society. The skeleton on which everything else rests. Societies and people alike require resources to exist, and no system is more effective for producing those necessary resources than strong property rights.
God may not directly value material wealth, but He, in his infinite wisdom, understands its importance to survival in our imperfect world. It is difficult to be a good person when you’re starving. The temptation to steal what you need to survive can be irresistible. It may be possible for some people to fight the urges and reach Heaven in spite of these hardships, but the resources available in a Just Society allow good, hardworking people to avoid the temptation through prudent decision making and to improve the Just Society for the next generation.
The incentives provided by strong protections for individual property rights drive people to maintain, improve, and innovate because they are rewarded for the fruits of their labor. Men who know their hard work will not be stolen by the degenerate masses of the lower class or the machinations of the upper class have the confidence to build, creating value where none existed before. They can then use this wealth to get a better wife than if they simply coasted through life, and to help set their children up for success.
While it is well known that great wealth is often connected to sins like decadence and corruption, this is typically the result of preexisting moral failings in a man willing to lie, cheat, and steal to acquire that wealth for its own sake. When a good man acquires great riches through innovation and excellence, he uses that wealth to build great works to improve the Just Society which made it possible for him to earn it in the first place. In many cases this means building new innovations which may deliver yet more profit for the good man while they improve society by creating goods, technologies, and productive jobs for other citizens. These indirect benefits can be difficult for the simple minded to understand, and evil men will always claim their predations are good, but in many cases, these projects deliver more benefit to the Just Society than obvious charitable works.
Unfortunately, property rights can never be truly absolute. A Just Society requires a government to regulate it, a strong military to protect it, and a justice system to thwart evildoers. While the government should be kept small to avoid trampling the personal freedoms that underpin a Just Society, it still requires resources to operate, and those resources must come from taxes. As a necessary evil, there is no perfect way to implement taxes. They will always cause harm to whatever they are applied to. In some cases, this can be turned into a benefit, such as taxing vices or unproductive industries like advertising, but this will rarely provide sufficient revenue, even after addressing more neutral luxuries like second houses. Taxes usually have to be applied to productive parts of society, and that requires sacrifices. The best guideline is to try to impact the essentials of day-to-day life as little as possible, and to try not to prevent innovators from carrying society forward, but both will usually be harmed to some degree.