How do you properly practice the more abstract precepts? The precept of killing is a great baseline. Very clear: if you kill something with intention, you break the precept. The factors I can remember in the kammic disecction of the matter are: the kammic weight of the one being killed, the intention of killing (and any coupling intents), the actual action, whether or not it succeeds, if, any, regret after the action, and maybe a few more factors. Giving each a realistic weight depending on the full situation will give you an average estimate of how bad it is.

The thing is that the actual action is very clear with killing no matter how obscure the situation. With precepts like stealing, lying, or practices like wrong speech there isn't really a meter to hold yourself to. I've asked around on reddit and even here before but I haven't had a proper, well-developed answer to this.

Some answers, particularly for right speech focus on following the heart or judging based on emotions, but that is the opposite of a discerning judgment and many of us follow our subtle judgement to worse kamma, not better.

A meter of 'that which is not freely given' is pretty good but refuted by the sutta that speaks of 'stealing' a flower's smell.

Other answers focus on a middle-ground, but these do not address the right course of action in situations where property becomes non-physical, or ownership of property splits, or other complex situations not faced during the Buddha's time.

At the end of the day, there is definitely a right answer to this question, and it's important to know it for this high-speed age. You need to know this before you find yourself in such a situation because the decision has to be made on the spot. The answer exists because to a Buddha's range, there is an absolute understanding of whether an appropriation of property is stealing or not. This absolute knowledge, assuming it is not the result of direct kammic vision, can be practiced by normal people too.

Edit: For a precept like stealing, ownership is arbitrary and can't be properly defined. Abusive speech is arbitrary and again changes from person to person. What might be a violation of right speech to one person isn't to another. Lying is pretty objective, but also has its' issues in getting proper communication across. In right speech, abusive speech is subjective: some consider certain words abusive, so if you speak to them in such a manner it won't be right speech. Others might not, and then there should be no violation of right speech in that situation even though everything you do is the same. So how do you find that line of practice where you can say, "I am properly keeping this or that precept, without worrying about self corruption?"
Because of the immense depth of the teaching, different skillsets/levels of students, and complexity/multidimensionallity of life in general, Buddhist theory and practice is a set of incremental approximations, from very coarse to more refined and precise. The provisional teachings are formulated in the narrative that makes sense to each particular student, such as the eastern religious narrative, or the narrative of shamanic mysticism, or the narrative of the mainstream society. More advanced teachings make use of the phenomenological narrative, the narrative of the subtle energies, and others. Some of the very advanced teachings require stepping outside of all narratives.

Since all people are different, all operate in different contexts, it is very difficult to make universal statements that mean the same thing to all people, have the motivating/inspiring effect in all the different contexts, and generally lead to positive outcomes in all of the endless "realities" (personal narratives).

The precepts are the lowest common denominator designed to work in all these different worlds. That is, they are meant to be the basic rule of thumb that works well enough regardless of the exact interpretation.

As individual practitioner, your understanding of precepts and of Dharma in general grows and matures - and transforms - during the entire journey. This is known as the transmutation of vows.


On the very basic level, you take precepts as is, without much thinking, and implement whatever they mean to you.
Then, you realize that precepts require you to control your mind and emotions: your "want" and "hate". So your context changes, instead of thinking in terms of external actions you think in terms of your mind states. At this point you don't painstakingly deliberate about individual precepts, you make sure your mind stays sober - as long as you do this, the precepts are "automatically" interpreted and executed in the right way.
Then, you get to the level where you no longer worry about your own goodness. Instead, your concern is about suffering and happiness of others. Just like on the previous level you stopped obsessing over individual precepts, on this level you're no longer obsessed with your mind state. You know, as long as you don't seek personal benefit, don't worry about personal difficulties, as long as you sincerely wish benefit for the others, then your mindstate will be alright, and your precepts will be taken care of.
Then, as you spend some significant time practicing the above, just as you hopefully did with every level (skipping levels in Buddhism is rarely a good idea) your understanding of ethics matures to the point when you understand the relative nature of any reference point. Because you now see that nothing has the absolute truth or the absolute value, you tend to be pretty cool about things, pretty dispassionate. So in your decision-making, you don't cling to any onesided position and you tend to prefer to act in such ways that helps others be less attached to their one-sided positions. So your ethical decisions of do/dont are now guided by your desire to promote wisdom, in-depth analysis, and certainly reduce possibilities of confrontation and conflict due to radicalized opinions, onesided judgements, attachments, and other forms of non-enlightened behavior, because you see that it leads to suffering. Just like the previous levels subsumed and transcended each other, on this level you abandon the notion of "doing good to others" - since good is not something that can be universally defined. So you no longer painstakingly obsess over the calculations of how much goodness will your actions bring to each of the affected participants of your action. Instead, your new rule of thumb is: as long as my actions are expressive of wisdom, promote non-attachment due to wisdom, dispassion due to wisdom - then the net effect will be good in all the different subjective universes.
At this point, you may realize that your personal karma limits your ability to be an expression of wisdom, and under direction of qualified teacher you decide to undertake Vajrayana deity generation practice or one of the other advanced practices. Because your understanding of emptiness has matured, you are no longer worried about getting stuck in any of the relative view points. So you learn to take on a particular relative point and hold on to that until you overcome your weakness in that area. At this point your precept is to maintain integrity of the relative point you have taken, regardless of what it does to the previous 4 levels. Once you complete your training, you can use various relative points effectively when dealing with people and students in different mental contexts. In other words, #5 is just a training trick to get better with #4. In reality #4 is the top level, so that's where you want to be.


You see? So you don't have to think in terms of the 5 precepts all the time. As your insight and practice matures, your context will change - but if your understanding is right then your actions that come from your new mental context will still be correct fulfillment of the vows taken on the previous levels. Generally speaking, if you do something on your current level that looks obviously wrong on a previous level - it means you got something very confused.

Makes sense? Sorry, I know you want clarity, you want clear guidelines that can help with your day to day decision making in support of your practice. This may not be the answer you expected, but I hope it will make things clearer for you. Let me know if you have specific examples you want to analyze.