A.T. Robertson Commentary Luke 4:43

"But he said unto them, I must preach the good tidings of the kingdom of God to the other cities also: for therefore was I sent." — Luke 4:43 (ASV)

I must (με δε). Jesus felt the urge to go with the work of evangelism "to the other cities also," to all, not to a favoured few.

For therefore was I sent (οτ επ τουτο απεσταλην). "A phrase of Johannine ring" (Ragg). Second aorist passive indicative of αποστελλω. Christ is the great Apostle of God to men.