Complex sentence: In 1955 he made a trip to Lebanon where he met Abd al-Hossein Sharafeddin, a meeting which was precedented in 1936 when Sadr's family had hosted Abd al-Husayn in Iran.
Split into simpler sentences: In 1955 he travelled to Lebanon where he met Abd al-Hossein Sharafeddin. He had met him previously in 1936 when his family had hosted Abd al-Husayn in Iran.