Zechariah 12:10a — "Then I will pour out (šāp̄ak) on the house of David and on the people of Jerusalem a spirit of grace and prayer" — shares its governing verb and its eschatological horizon with Joel's promise, "I will pour out (šāp̄ak) My Spirit on all people" (Joel 2:28). Both prophets reach for the same prophetic Spirit-outpouring topos — šāp̄ak of the rûaḥ, set within the Day of the LORD — yet the wording is not borrowed verbatim (Joel pours the Spirit on all flesh for prophecy, dreams, and visions; Zechariah pours a spirit of grace and supplication on the house of David for looking and mourning), which makes this an Echo of a common stock rather than a citation or formal allusion. Read together they describe one outpouring under two aspects: Joel names the Spirit in His proclamatory mode (sons and daughters prophesying, everyone who calls on the name of the LORD saved, 2:32), Zechariah names the same Spirit in His convicting mode (grace that opens the eyes to the pierced One and breaks the heart over Him). The two prophecies converge historically at Pentecost, where Peter cites Joel explicitly (Acts 2:17-21) while the hearers, disclosed their crucified Messiah, are "cut to the heart" (Acts 2:37) — the looking-and-mourning of Zechariah enacted by the very Spirit Joel announced. The longitudinal theme is not typology: no person, event, or institution prefigures another here; rather a single canon-wide motif (the promised effusion of the eschatological Spirit, Ezek 39:29; Isa 32:15; 44:3) is carried forward by two prophets who develop its complementary registers. The telos lands in Christ as desirable: the same outpoured Spirit who convicts of having pierced Him is the Spirit of grace — so that the mourning is itself a gift, and the One we grieve to have wounded becomes, by that grace, the One we cannot help but behold and savor.