These may not be what you think. If the good is what accords with truth and evil is what deviates from that then they are certainly not what most people think. For most people entirely disregard the spiritual and even those who think they believe in the spiritual usually put it behind the material/worldly/human in practical terms. They define good by worldly good but if worldly good puts itself above spiritual good or even ignores the prior claim of spiritual good then it is evil. Jesus came to save souls not to set up the perfect human society. In fact, he seemed to have had no interest in that at all which may have been why Judas turned against him, Judas being a typical modern person more interested in political change than spiritual awakening.
But let's go back to basics. If there is no spiritual is there even any such thing as evil? There is bad, certainly, but evil implies something more than bad. It is not just destruction of material things, the body, physical life, for personal advantage but destruction of essence, and essence is spiritual. Bad is the opposite of good but evil actively works against good, seeking to undermine it, pervert it, corrupt it, destroy it because of hatred. Perhaps just as good is love so evil is hatred and if hatred is love deformed and turned against itself so evil bears the same relationship to good which is to say that good is the reality and evil is that reality gone wrong.
What I am saying is that good and evil are spiritual concepts, concepts rooted in a far deeper reality than just the material world. So, if you deny the spiritual you really have no business talking about evil. Conversely, if you accept evil you must acknowledge the spiritual, and if you acknowledge the spiritual you must see it as primary and the material as its support. We have reversed this relationship and reduced the spiritual to either nothing, an expression of the material or, as with most followers of religion, something to be defined in terms of the material.
For practically everybody today good is material good, what increases material comfort and reduces material suffering. Evil is what does the opposite regardless of other considerations. This partly explains the extraordinary behaviour over the last year. But this was not how Jesus saw it. Good was what did the will of his Father which was bringing souls back to him. Jesus healed the sick and fed the hungry but not very often and probably only to demonstrate the reality of divine power. What he did continuously was preach the kingdom of God and tell us how to get there. He was concerned with spiritual good more or less to the exclusion of anything else.
At the moment there is an all-out assault on spiritual good not by attacking it directly but by replacing it with a lower good or, better put, a false good, a good that relates to human beings as they are in this world and, by virtue of that, seeks to keep them and their attention in this world. This false good denies the soul, the spiritual component of man, and that makes it evil in the true spiritual sense. So, this is not evil as obvious wickedness but evil masquerading as good in order to destroy the true good. It is Satan appearing as an angel of light.
Any morality not centred in God or, at the very least, a higher reality is actually immoral. This is because it creates and reinforces a false good so blocking out the true good and preventing growth in that good. Paradoxically, the strictest adherents of such a morality are the most spiritually immoral.
What people need to understand now is that the nature of evil has changed. Now, it has moved from being principally a material thing (murder, violence, lying, cheating etc) to being a spiritual thing - denial of God. Or reality since God is reality. And this denial can only come from a misaligned spiritual will so it is never innocent. The old evils still remain, of course, but a deeper sin has been added to them, all the worse for not being regarded as such.
The difficulty for so many people is that good and evil are not clear so millions of ordinary, decent people (decent by conventional standards) are actually on the side of evil. But that is because we look at good and evil in materialistic terms rather than, as we should, spiritual terms. Once you start thinking of the material world as a place designed to bring out spiritual choice then everything becomes a lot more obvious.
Most people want to be good but for that to be possible you have to know what good is and for that to be the case the heart must be rightly oriented. Our hearts are not rightly oriented and that is our own fault.
To sum up, let me say that whether you are for good or evil now depends on whose side you are on. God and creation or the world as it is presented in current belief systems, some of which are actually religious. It is not so much whether you are a conventionally good or bad person, though clearly you should always seek to be good and sincerely repent your failures. It is determined by whether your heart inclines towards God or the teachings of this world which deny God. And if you are not for God then, as the scripture says, you are against him. There is no neutral ground, certainly not any longer. This should be a wake up call to the millions of people who just go along with things as they are. You cannot now say "It's not my fault. It's how things are. I can't be held responsible if I just do as others do." The truth is always within you. You are responsible.
This post echoes recent ones by Bruce Charlton and Francis Berger though most of it was written before I read those. I believe this indicates there is something in the air now saying that a serious choice is being demanded of us and we need to make that choice soon.