قَالَ اَلصَّادِقُ عَلَيْهِ اَلسَّلاَمُ: «اَلصَّلاَةُ ثَلاَثَةُ أَثْلاَثٍ ثُلُثٌ طَهُورٌ وَ ثُلُثٌ رُكُوعٌ وَ ثُلُثٌ سُجُودٌ.
Imam Jafar ibn Muhammad Al-Sadiq (a.s) said: "The prayer consists of three parts: one-third is for purification, one-third is for bowing (ruku), and one-third is for prostration (sujud) "