The human being as citizen of the world
The idea that we all are active members of Spaceship Earth can be made to derive from very ancient religious and philosophic teaching, as shown in these short passages from Epictetus.
This is worth reminding especially when there is a resurgence of nationalism and chauvinism that is always very damaging for everybody (morally, socially, economically).
If the things which are said by the philosophers about the kinship between God and man are true, what else remains for men to do than what Socrates did, namely, never reply to the question: "to what country you belong" to say that you are an Athenian or a Corinthian, but that you are a citizen of the world. For why do you say that you are an Athenian, and why do you not say that you belong to the small nook only into which your poor body was cast at birth? Is it not plain that you call yourself an Athenian or Corinthian from the place which has a greater authority and comprises not only that small nook itself and all your family, but even the whole country from which the stock of your progenitors is derived down to you?
He then who has observed with intelligence the administration of the world, and has learned that the greatest and supreme and the most comprehensive community is that which is composed of men and God, and that from God have descended the seeds not only to my father and grandfather, but to all beings which are generated on the earth and are produced, and particularly to rational beings - for these only are by their nature formed to have communion with God, being by means of reason conjoined with Him - why should not such a man call himself a citizen of the world, why not a son of God, and why should he be afraid of anything which happens among men?
Discourses, Book I, 1-6