2. Al-Husayn ibn Muhammad has narrated from Mu‘alla’ ibn Muhammad, from al-Washsha’ from Aban ibn ‘Uthman, from ‘Umar ibn Yazid who has said the following: “I once asked abu ‘Abd Allah , about a traveler who performs Salah (prayer) behind an Imam and joins only for two Rak‘at, is it sufficient? He (the Imam) said, ‘Yes, it is sufficient.’”