van der Merwe, Dirk. "Conceptualising Holiness in the Gospel of John: The Mode and Objectives of Holiness (part 1)." HTS Teologiese Studies 73 (3) 2017, a3421.
Van der Merwe investigates terminology used to describe holiness in John's Gospel so as to evaluate the overall concept as used in John. He reviews use of the adjective ἱερός, indicating sacral purity and a state of being worthy of reverence, ὅσιος, indicating a relationship to divine command and human obedience (van der Merwe 2017, 1), and ἅγιος, indicating a duty to worship a holy thing (van der Merwe 2017, 2). By his analysis, ἅγιος, the only one of the three adjectives used in John, refers to the holiness of the persons of the Godhead. Van der Merwe thus evaluates first "the theological environment…(then) the code of holiness and lastly the objectives for holiness in the Gospel of John" (van der Merwe 2017, 2).
Van der Merwe evaluates in turn passages in John's Gospel in which the ἅγι… word group is used, including John 17:11 (van der Merwe 2017, 2), where the holiness of God protects and unfiies His people; John 6:69, where Jesus is identified as the holy one belonging to God (van der Merwe 2017, 3); John 1:33, 14:26, and 20:22, where the Holy Spirit makes God's people recognizable and directs them to Jesus, equipping them to carry on Jesus' work (van der Merwe 2017, 4); and 10:36 and in chapter 17, where, using the verb form, Jesus expresses the consecration of himself and his disciples for their mission (van der Merwe 2017, 4).
Building on his concept of the holiness of God, van der Merwe finds a code of holiness for Jesus' followers articulated in John 17:20-23 (van der Merwe 2017, 5). The code is signified by repetitive language which refers to unity. In the passage, the holy unity of the Godhead is used to extrapolate the unity as the necessary characteristic of the disciples. The necessary unity of the Father and the Son is critical to John's Gospel and serves as a sign of holiness (van der Merwe 2017, 6). Christians take on unity with one another as they take on the character of the unified, holy God who dwells in them.
The specific actions of hiliness are not spelled out in John 17. However, van der Merwe evaluates the actions involved in positive interactions between Jesus and his disciples throughout the Gospel so as to see objectives which may exist in the sanctification process (van der Merwe 2017, 7). The objectives he reviews are ἵνα clauses ("so that"). He catalogs unity (17:20-23), loving obedience (15:9-17), bringing light to the world (1:9) (van der Merwe 2017, 8), and revealing the glory of God (17:4).
Van der Merwe thus concludes that, in John's Gospel, the unity of Christians is derived from the unity of the Godhead and results in Christians participating in the work of bringing that unity, and thus God's holiness, to their world.