Complex sentence: The Caliph al-Ma'mun wanted al-Jāḥiẓ to teach his children, but then changed his mind when his children got afraid of his boggle-eyes (جاحظ العينين), it's said that this is where he got his nickname.
Split into simpler sentences: The Caliph al-Ma'mun wanted al-Jāḥiẓ to teach his children, but then changed his mind when his children got afraid of his boggle-eyes (جاحظ العينين). It's said that this is where he got his nickname.