In the OT, the Spirit is susceptible to a mere dynamistic or impersonal interpretation, as simply representing Yahweh’s divine presence or power. In the NT, the Spirit appears in dynamistic mode, as the power of the Father or Son. In the book of Acts, the Holy Spirit speaks (1:16), is lied to (5:3), is tempted (5:9), bears witness (5:32), is resisted (7:21), snatches (8:39), sends (13:4), thinks good (15:28), forbids (16:6), prevents (16:7), and appoints (20:28) – all personal acts. The Spirit can also be blasphemed (Mark 3:28-9; 12:32), which requires for the Spirit both a personal and a divine identity.
There are no biblical texts that explicitly identify the Spirit as God. In the OT, the Spirit plays an integral role in creation (Gen. 1:2), and the Holy Spirit plays a vital role in judgment (John 16:8-11) and in re-creation (John 3:5-8). The new creation is a pervasive soteriological theme in the NT; this includes the Spirit in the work of salvation, which, as with other divine functions, can be performed only by God, even though the Spirit is never explicitly called Savior.
It was John that portrays the Holy Spirit when he depicts Jesus stating that after his departure, the Father will send (literally) “another paraclete,” implying that the Son is the first Paraclete. The Spirit is the Paraclete who proceeds from the Father (15:26) and is sent by Christ (16:7) to glorify the Son (16:14) by way of hearing and speaking what Christ directs (16:13-14), teaching and reminding disciples (14:26), and convicting and judging the world (16:8-11).
The Holy Spirit is the paraclete Jesus promised at his ascension, the advocate, encourager, and counselor. Paul calls the Holy Spirit the “spirit of adoption” because the Spirit is the “bond” that unites us to Christ in adoption as sons and daughters of God, meaning we are united with Christ in his death and resurrection. Salvation, then, means adoption as a child of God, which comes only through union with Christ through the Holy Spirit.