1 Here δέ (de) has not been translated.
2 Grk “he”; the referent (Jesus) has been specified in the translation for clarity.
3 An aorist participle preceding an aorist main verb may indicate either contemporaneous (simultaneous) action (“When he called … he gave”) or antecedent (prior) action (“After he called … he gave”). The participle συγκαλεσάμενος (sunkalesamenos) has been translated here as indicating antecedent action.
4 Some add ἀποστόλους (apostolous, “apostles”; א C* L Θ Ψ 070 0291 f13 33 579 892 1241 1424 2542 lat) or μαθητὰς αὐτοῦ (mathētas autou, “his disciples”; C3 al it) here, but such clarifying notes are clearly secondary.
5 Note how Luke distinguishes between exorcisms (authority over all demons) and diseases here.

In other versions

And he called the twelve together and gave them power and authority over all demons and to cure diseases,

When Jesus had called the Twelve together, he gave them power and authority to drive out all demons and to cure diseases,

Summoning the Twelve, he gave them power and authority over all the demons and to heal diseases.

One day Jesus called together his twelve disciples and gave them power and authority to cast out all demons and to heal all diseases.

And summoning the twelve, he gave them power and authority over all the demons and to cure diseases,

Then he called his twelve disciples together, and gave them power and authority over all devils, and to cure diseases.

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