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".
fate (xrew/n) "deceived" him (a)pathqei/j; Ant. 8.420; cf. 8.409)67. Thus, according to Josephus, fate and providence were sometimes administered by supernatural beings.
The Talmud recounts a story of how an angel assists in setting certain aspects of a person’s destiny just prior to conception:
The angel appointed over conception is named Lailah. He takes a seminal drop, sets it before the Holy One, blessed be He, and asks, ‘Sovereign of the Universe! What is to become of this drop? Is it to develop into a person strong or weak, rich or poor?’ But no mention is made of its becoming a wicked or righteous person (Nid 16a)68.
Whereas health and social class are predetermined, a person’s free moral agency is preserved69.
The Essenes, Josephus, and the Talmud endorse the concept of predestination, even though they differed over whether or not free will exists. They also agree that angels were sometimes involved in the inner workings of predestination 70. This helps to explain why the Sadducees would have objected to the operation of angels and spirits (good or evil) in the universe.
2. Criterion Two: The Distinction Between Angel and Spirit
The distinction between angel and spirit could be accounted for in several ways. One possibility is that angels are contrasted to human spirits. If "spirit" refers to disembodied humans prior to resurrection, as Daube suggested, then this fits well with the Sadducean denial that the soul survives the death of the body. This definition also fits well in the context of Acts 23,8-9, where it would mean that the Sadducees did not believe that the spirit of a dead person visited Paul, whereas the Pharisees, or other Jews of the day, would not have hesitated to believe in a message from beyond the grave71.