This is a known issue. Abandoned quests stay in the system and get flagged as if still present, but you don't need to go see a quest giver. Selecting another quest clears the text out of the quest log.
Seems to be more than a few quest bugs.
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Abandoned quest should no longer update. Fixed since.
"The psychological trials of dwellers in the last times will be equal to the physical trials of the martyrs. In order to face these trials we must be living in a different world."