1 sn A quotation from Exod 12:46, Num 9:12, and Ps 34:20. A number of different OT passages lie behind this quotation: Exod 12:10 LXX, Exod 12:46, Num 9:12, or Ps 34:20. Of these, the first is the closest in form to the quotation here. The first three are all more likely candidates than the last, since the first three all deal with descriptions of the Passover lamb.
2 sn A quotation from Zech 12:10. Here a single phrase is quoted from Zech 12, but the entire context is associated with the events surrounding the crucifixion. The “Spirit of grace and of supplication” is poured out on the house of David and the inhabitants of Jerusalem in the first part of v. 10. A few verses later in 13:1 Yahweh (typically rendered as “Lord” in the OT) says “In that day a fountain will be opened for the house of David and for the inhabitants of Jerusalem, for sin and for impurity.” The blood which flowed from Jesus’ pierced side may well be what the author saw as the connection here, since as the shedding of the blood of the sacrificial victim it represents cleansing from sin. Although the Jewish authorities and Roman soldiers certainly “looked on the one whom they have pierced” as he hung on the cross, the author may also have in mind the parousia (second coming) here. The context in Zech 12-14 is certainly the second coming, so that these who crucified Jesus will look upon him in another sense when he returns in judgment.