I'll just quickly mention some parallels that former Protestant pastor and Biblical scholar Scott Hahn points out between the first chapter of Luke and the 6th chapter of 2nd Samuel, where Luke calls up imagery from David's moving of the Ark and Mary's journey to Elizabeth.
Both "arose and went" (2 Sm 6:2, Lk 1:39) into the same hill country. Both Elizabeth and David feel unworthy (2 Sm 6:9, Lk 1:43) and ask a similar question. The unborn John leaps (Lk 1:41,44) and David leaps and dances (2 Sm 6:16). Both Mary and the Ark stay for 3 months (Lk 1:56, 2 Sm 6:11). In Lk 1:42, Luke uses the same verb for Elizabeth's exclamation as the Old Testament verb used by the levites for chants of praise to God, which is significant because Elizabeth is of Levitical descent (Lk 1:5). The verb is not used elsewhere in the New Testament and is used in the Old Testament only in describing events related to the Ark of the Covenant. Now protestants reading this may say I'm grasping at straws. When I was protestant, I might have agreed with them. But in the Catholic method of reading scripture, these are not mere trivialities.
Great post.