Dunya (world)
Al-Sheikh Al-Sadooq through his chain of narrators, narrated from Imam Ali (a.s) that the Messenger of God (s.a.w) said:
The worst of the absentminded people are those who do not learn from the changes of dunya.
The worst of those who are in danger in dunya are those who do not consider any danger upon themselves in this dunya.
Dunya = world, wordly life
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Source: Biharul-Anwaar, vol. 77, p.113