After the prophets, there arose from time to time a hope of the dawning of a new age, especially within the apocalyptic
movement, which generally pointed to the Messiah or a prophetic reawaking of some kind. The messianic expectation of Judaism included the eschatological outpouring of God’s spirit (e.g., 1 Enoch 49:3, citing Isaiah 11:2). Qumran literature identifies the spirit of prophecy with “God’s Holy Spirit” (1QS 8.16; Zadokite Documents II.12).
In Judaism, wisdom is full of spirit and is identified with the Spirit (Wisdom of Solomon 7:22; 9:1; cf. 1:5). Accordingly, intertestamental Judaism understood messianic Spirit of the Lord to be the Holy Spirit, that spirit which had foretold through the prophets that the coming Messiah would inaugurate the age of salvation with the outpouring of the Spirit on all flesh (EVDT 522).