{Because that of long time he had amazed them with his
sorceries} (dia to hikan(9369) chron(9369) tais magiais exestakenai
autous). Causal use of dia with the accusative articular
infinitive (perfect active _Koin(825f) form and transitive,
exestakenai). Same verb as in verse  9  participle existan(936e)
and in verse  13  imperfect passive existato (cf. also  2:7 
already). Chron(9369) is associative instrumental and magiais
instrumental case.