Matthew and Mark each record two feeding stories (Feeding of the 5000 = Mt 14:13-20//Mk 6:30-44 and the Feeding of the 4000 = Mt 15:32-39//Mk 8:1-10), plus a retrospective passage on them (Mt 16:5-12/Mk 8:14-21), while both Luke and John record only the feeding of the five thousand (Lk 9:10-17; cf. Jn 6:1-14). Therefore, neither Luke nor John record a retrospective passage on two feedings since they each have only one. On the Two Gospel (neo-Griesbach) Hypothesis, Mark would have had access not only to Matthew's gospel, but also to Luke's. And if Mark had access to Luke's first volume, then it is not unlikely, providing that relative or absolute dating would allow it, that Mark would have also had access to Luke's second volume, the Acts of the Apostles. While assuming the validity of the Two Gospel Hypothesis, this paper will argue that Acts 6:1-6 is the clue to understanding (1) Mark's choice to include two feedings in his gospel, as did Matthew, in contrast to Luke, and (2) Mark's choice to change Matthew's focus in his retrospective passage on the Pharisees and Sadducees as the "leaven" which members of the earliest Jewish Christian community are to avoid to an end focus on numerological speculation about the significance of the number of baskets remaining from each of the two feedings (the 12 and the 7) one feeding each for the more original Jewish Christian community (the 5000, the 12, cf. Acts 6:2) and the more Gentile oriented early Christian community (the 4000, the 7, cf. Acts 6:3). The way the two feedings and the retrospective passage upon them are woven intimately into the literary fabric of both Matthew and Mark make these passages, short of comparative analyses of the whole texts of the synoptics, some of the most important in determining literary relationships among the synoptics.