be sanctified - consecrated. The only difference between the application of the same term to Christ and the disciples is, as applied to Christ, that it means only to “consecrate”; whereas, in application to the disciples, it means to consecrate with the additional idea of previous sanctification, since nothing but what is holy can be presented as an offering. The whole self-sacrificing work of the disciples appears here as a mere result of the offering of Christ [Olshausen].
through - in.
the truth - Though the article is wanting in the original here, we are not to translate, as in the Margin, “truly sanctified”; for the reference seems plainly to be “the truth” mentioned in Joh 17:17. (See on Joh 17:17).