Ramadan - Paradise Open & Hell Closed (Ahadith 1617 - 1618)

Volume 3, Book 31, Number 122:
Narrated Abu Huraira (radiallaahu `anhu):
Allah's Apostle (sallallaahu `alayhi wasallam) said, "When Ramadan begins, the gates of Paradise are opened."

Volume 3, Book 31, Number 123:
Narrated Abu Huraira (radiallaahu `anhu):
Allah's Apostle (sallallaahu `alayhi wasallam) said, "When the month of Ramadan starts, the gates of the heaven are opened and the gates of Hell are closed and the devils are chained."
Opening of the gates of Paradise means that the way to Paradise and its attainment is made easier through deeds like praying, fasting and reciting Quran etc. Similarly, closing of the gates of Hell means that the way to Hell is made tougher by making it easier to leave sins - chaining of the devils helps in both scenarios, since they're not around to whisper in our hearts and encourage us to commit bad deeds.
Alhamdulillah for Ramadan and its blessings. May Allah make us all come out of it sinless. Ameen.

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