Shabib b. Abu Rauh reported on the authority of one of the companions of God’s messenger that God’s messenger prayed the morning prayer and recited Ar-Rum*, but became confused about it. When he finished the prayer he said, “What is the matter with people who pray along with us without performing the purification properly? It is only those who cause us confusion about the Qur’an.”
*Qur’an, xxx.
God's messenger counted them in my hand, or in his hand, saying, “The glorifying of God is half the scale,
‘Praise be to God’ fills it, ‘God is most great’ fills the space between heaven and earth, fasting is the half of endurance, and being purified is half of faith.”
Tirmidhi transmitted it and said that this is a hasan tradition.