Luke 9:55 - Ellicott's Commentary On The Whole Bible

Ye know not what manner of spirit ye are of. — The words admit of two constructions: (1) that the disciples did not know that the Spirit that had been given “not by measure” to their Master, and promised by Him to them (Matthew 10:20; John 3:34), was one of gentleness and love; (2) that they did not know that in yielding to what they thought a righteous anger, they were really yielding themselves to the evil mind, or the personal Evil Spirit which was at enmity with God. Looking to the general use of the word “spirit” in our Lord’s teaching, the former way of taking the words seems, on the whole, preferable, and agrees better with what follows. The Spirit which had claimed them for its own was one that led Him to save and not to destroy. The whole clause, however, is wanting in the best MSS.