Imam Hasan Al-Askari (PBUH) who is from the descendant of Imam Hussain and the prophet Muhammad (PBUH) has said:
“The signs of a believer are five:
1.Performing 51 units of prayer [1] [of which 17 units are the obligatory prayers and 34 units are the recommended prayers per day]
2. Pilgrimage of Imam Hussain (PBUH) on Arbaeen [the 40th day following Ashura],
3. Wearing a ring on the right hand,
4. Placing the forehead on the earth [during Sajdah in the prayer];
5. Saying “Bismillahir Rahmanir Rahim” [which means “In the name of God, the compassionate, the merciful”] aloud during the prayer “[2]
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[1] Each prayer or Salat in Islam consists of individual units called Rakat. Each Rakat is very similar to each other except some minor details.
[2] References: Tahzib Al-Ahkam: V.6 , P.52; Mesbah Al-mojtahid: p.73