This may have suggested to the thoughtful Hebrew that the Spirit is God and is a personality distinct from Him from whom He proceeds.
The only other Old Testament designation is the Holy Spirit. This occurs only in Ps. li. 11 and Isa. lxiii. 10, 11. In the New it is very common. The adjective holy cannot be distinctive of the quality of purity which is not found in equal degree in the Father and the Son. Both are holy. Hence, as it is not descriptive of an attribute peculiar to the Spirit, we infer that it points to the peculiar office of the Spirit, in the redemptive scheme, to make men holy. The Holy Spirit, then, is the scriptural term for the Sanctifier, a term not found in the scriptures as a designation of the Spirit.
Holy Spirit is a name in English preferable to Holy Ghost, for the reason that words like men flourish and decay. Ghost and ghostly were once dignified words, as "ghostly adviser" for spiritual adviser. But these words have become degraded so that it would sound strange to us and repulsive to hear the words "the Ghost of God." Hence we commend the American revisers for substituting uniformly Holy Spirit for Holy Ghost.
— edited from The Gospel of the Comforter (1898) Chapter 1.