"I was sent only to the lost sheep of the house of Israel" (Mt 15:24).Yes, Jesus on earth ministered to Israel (and the centurion, and the woman with crumbs/table, and the Samaritan woman) but that does not mean that's ALL He was sent for.
Um, Jesus isn't sending himself out to make disciples of nations, now, is he."Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age.”--Matthew 28:19-20