Floyd Parker, «The Terms "Angel" and "Spirit" in Acts 23,8», Vol. 84 (2003) 344-365
In any discussion of the Sadducees, there will always remain a certain amount of doubt due to the paucity of sources about them. Based on what data has survived, the older theory that the Sadducees rejected the extravagant beliefs about angels and spirits provides the most convincing solution to the problem of Acts 23,8. The Sadducees’ reasons for rejecting these views were twofold: 1) angels were integrated into the apocalyptic world view that they rejected; and 2) angels often served as God’s servants to administer predestination or providence. Thus, when Paul claimed that a heavenly being had appeared to him in a manner and with a message that appeared to be predestinarian in nature, the Sadducees were unwilling to entertain the idea that an angel or spirit had appeared to him. Certainly new theories will arise in an attempt to grapple with this issue, but to re-appropriate the words of Jesus in Luke 5,39, "the old is good enough".
Pharisees allow for a mixture of fate and free will (Ant. 13.171-173; 18.13; BJ 2.162-165). Since Josephus’ view of fate has been described as "the executive aspect of the Divine will"61, one might well ask through what agencies the divine plan was specifically carried out in history and nature. One method was to employ various types of messengers, particularly prophets62 and angels. The latter group will be the focus of the rest of this section.
In the Dead Sea Scrolls, angels are administrators of predestination:
He has created man to govern the world, and has appointed for him two spirits in which to walk until the time of His visitation: the spirits of truth and injustice ... For it is He who created the spirits of Light and Darkness and founded every action upon them and established every deed [upon] their [ways]" (1QS 3.17b-24a; 1QS 3.25b-26a)63.
Thou hast decreed for us a destiny of Light according to Thy truth. And the Prince of Light Thou hast appointed from ancient times to come to our support; [all the sons of righteousness are in his hand], and all the spirits of truth are under his dominion (1QM 13.9b-10).
In these texts God has predetermined that each person will be under the dominion of the two spirits, as in the first passage, or be influenced by them for good or evil, as in the second64.
In Josephus’ reshaping of the biblical narratives, fate and providence sometimes take over the functions previously performed by angels65. In the story of Daniel, the angel who shut the mouths of the lions (Dan 6,22) is replaced by "the Deity and His Providence" (to_ qei=on kai_ th_n tou/tou pro/noian; Ant. 10.260; cf. 262)66. Likewise, the three young men are not rescued from the flames of the furnace by one who looked like "a son of god", as in Dan. 3,25, but by "divine providence" (qei/a| sw/zontai pronoi/a|; Ant. 10.214). Instead of a lying spirit (pneu=ma yeude/j; 1 Kgs 22,22.23 LXX) entering the mouth of false prophets to "deceive" (a)path/sei) Ahab (1 Kgs 22,20.22 LXX),