We are largely confined to private worship because of a lack of resources. Due to persecution, our late antiquity ancestors were increasingly forced to worship the gods in private as well. So there is this continuity between us and them in that sense. It is up to us to rediscover practice in the public sphere again.

“With regard to whatever objects give you delight, are useful, or are deeply loved, remember to tell yourself of what general nature they are, beginning from the most insignificant things. If, for example, you are fond of a specific ceramic cup, remind yourself that it is only ceramic cups in general of which you are fond.”

Epictetus, The Handbook, 3

If we love the forms or essences of things rather than particular instantiations of those essences, we will not be made miserable by the inevitable end of the particulars.

"Hymn of the Pythagoreans to the rising sun" by Fyodor Bronnikov (1869)

"Sin should be abstained from, not through fear, but for the sake of the becoming."

The Golden Sentences of Democrates

When you are going about any action, remind yourself what nature the action is. If you are going to bathe, picture to yourself the things which usually happen in the bath: some people splash the water, some push, some use abusive language, and others steal. Thus you will more safely go about this action if you say to yourself, "I will now go bathe, and keep my own mind in a state conformable to nature." And in the same manner with regard to every other action. For thus, if any hindrance arises in bathing, you will have it ready to say, "It was not only to bathe that I desired, but to keep my mind in a state conformable to nature; and I will not keep it if I am bothered at things that happen."

Epictetus, The Handbook, 4

The universe is a shrine for the gods. (Cf. Plato, Timaeus 37c)

Plato emphasizes mathematics in his education of the upper classes, as described in the Republic. While mathematical knowledge has practical benefits, it is to be studied for its own sake, as it aids us in “knowing what always is, not what comes into being and passes away” (Republic 527b).

Be mathematically literate.

Men are disturbed, not by things, but by the principles and notions which they form concerning things. ... When therefore we are hindered, or disturbed, or grieved, let us never attribute it to others, but to ourselves; that is, to our own principles.

Epictetus, The Handbook, 5

The universe is always happy; and our soul will likewise be happy, when it is assimilated to the universe; for thus it will be led back to its cause. Hence, when the sensible man is assimilated to the universe, he also imitates his paradigm after an appropriate manner, becoming a world through similitude to the world, and happy through resemblance to that blessed God, the universe.

Proclus, Commentary on the Timaeus, Book I

Consider both the praise and the reproach of every foolish person as ridiculous, and the whole life of an ignorant man as a disgrace.

The Pythagoric Sentences of Demophilus

Don't be prideful with any excellence that is not your own. ... What, then, is your own? Only your reaction to the appearances of things. Thus, when you behave conformably to nature in reaction to how things appear, you will be proud with reason.

Epictetus, The Handbook, 6

In other words, be proud of how you respond, think, and act but not of, for example, the things you own.

In Platonism, the world is considered beautiful and as good as it possibly could be, despite its imperfections.

Indeed, to understand the cosmos is, in an important sense, to understand divinity. This is why the Greeks were lovers of mathematics and science.

At the same time, we are not to attach ourselves to the lower elements of physicality, and our passions and instincts should always be ruled over by discipline and wisdom.

Enjoy the world around you but always be prepared to give it and things in it up. (Cf. Epictetus, The Handbook, 7)

"The fully actualized soul, from a Platonic perspective, becomes a kind of cooperating junior partner, so to speak, with the gods in bringing order to the cosmos. And so when we bring order to our inner psychic cosmos, we are cooperating in the gods' own cosmogonic work. We're cooperating in that labor of demiurgy."

Edward Butler, https://youtu.be/cRU8Qh-kYhE

Don't demand that things happen as you wish, but wish that they happen as they do happen, and you will go on well.

Epictetus, The Handbook, 8

In modern times, a philosopher is some sterile academic. But a true philosopher, a philosopher in the Hellenic tradition, is much more like a sage or a Vedic rishi.

Sickness is a hindrance to the body, but not to your ability to choose, unless that is your choice. Lameness is a hindrance to the leg, but not to your ability to choose. Say this to yourself with regard to everything that happens, then you will see such obstacles as hindrances to something else, but not to yourself.

Epictetus, The Handbook, 9

With every accident, ask yourself what abilities you have for making a proper use of it. If you see an attractive person, you will find that self-restraint is the ability you have against your desire. If you are in pain, you will find fortitude. If you hear unpleasant language, you will find patience. And thus habituated, the appearances of things will not hurry you away along with them.

Epictetus, The Handbook, 10

"The soul reasons best when none of these senses troubles it, neither hearing nor sight, nor pain nor pleasure, but when it is most by itself, taking leave of the body and as far as possible having no contact or association with it in its search for reality."

Plato, Phaedo 65c