This is a Madani Surah revealed between the 4th and 5th year of Hijrah - time between the Battle of Badr and the Treaty of Hudaibiyah.  The Surah has 29 verses in 4 sections.

The Surah was revealed during the period when the non-believers attacked the tiny Islamic State from all sides.  It encourages Muslims to make sacrifices for their faith and be aware of the non-believers as well as the hypocrites in their own ranks.

Recitation: Shaykh Mishaari Raashid & Ibrahaim Walk using Saheeh International Translation. Thematic introduction: Dr. Muzammil H. Siddiqi.