You made me think of a favorite passage of mine from the Bible. The versions vary depending upon the Bible you happen to have at hand, casting a slightly different light on the thought, but they all basically reflect a common sentiment. My favorite version is probably the one I was initially introduced to, in the King James Bible:
1 Chronicles 29:15
"For we are strangers before thee, and sojourners, as were all our fathers: our days on the earth are as a shadow, and there is none abiding."
It's a recognition of our status as temporary beings, emphasizing the importance of that recognition. I've felt a sojourner all my life.
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