ANSWER: There are not two words, but one word with two meanings, both of which are in this text: "I set apart of consecrate myself to the salvation of believers in order that they may be truly sanctified, cleansed from all defilement." This is the meaning of "in truth," as also in Matt. 22:16, Col. 1:6, II John 1:1, III John 1. In Luke 17:33 Christ uses "life" with two meanings. In II Cor. 5:21, "sin" is used first as guilt and secondarily as a sin-offering. This use of a word with two meanings was regarded by Hebrew writers as rhetorical elegance. Christ had no need to be truly sanctified because he had no sin. The depraved tendencies of believers need entire sanctification.
— Steele's Answers pp. 208, 209.