1 Thessalonians 4:8

He therefore that despiseth, despiseth not man, but God, who hath also given unto us his holy Spirit. Despiseth, [ ho (G3588) athetoon (G1140)] - 'setteth at nought' such duties of his calling (1 Thessalonians 4:7); in relation to his brother (1 Thessalonians 4:6). He who doth so 'sets at nought not man, but God' (Psalms 51:4). As the verb in Luke 10:16; John 12:48 is used of rejecting God's minister, it means so here.

Who hath also given unto us. So A C f g, Vulgate. But 'Aleph (') B G read 'who giveth (present) unto you' (not "us"). The "also" in 'Aleph (') C G g, Vulgate. Besides having "called us in holiness" (1 Thessalonians 4:7), He 'also gives us His Spirit' to realize it. The giving of the Spirit is continually going on.

His ... Spirit, [ To (G3588) Pneuma (G4151) autou (G846) to (G3588) hagion (G40)] - 'His Spirit, the Holy (one);' emphatically marking "holiness" (1 Thessalonians 4:7) as His Spirit's attribute; and so His Spirit's office to impart to believers. 'Unto you,' as its objects; given unto, into, or within, and among you (cf. 1 Thessalonians 2:9; Ephesians 4:30). Giveth: sanctification is, not merely once for all accomplished in the past, but present and progressive. So the Church of England Catechism, 'sanctifieth (present) all the elect people of God.' "His:" He gives you that which is essentially identical with Himself, that you should become like Himself (1 Peter 1:16; 2 Peter 1:4).