According to Luke 2:32, Simeon refers to Christ as "a light of revelation to the Gentiles," which is almost certainly an allusion to Isa 49:6 ("I will also make You a light of the nations").
According to Acts 13:47, Paul responds to Jewish opposition to his gospel message by claiming that the Lord commanded he and Barnabas, followed by a citation from Isa 49:6 ("I have placed you as a light for the Gentiles, that you may bring salvation to the ends of the earth").
So in Luke 2:32, Luke seems to indicate that Christ is the fulfillment of Servant in Isa 49:6, while in Acts 13:47 he seems to present Paul and Barnabas as the fulfillment of that same Servant passage. On what basis, then, does Luke assert that both are true? In other words, what is the underlying theological logic that allows Luke to make such claims?