The thirty pieces of silver would be used to buy the Potter's Field.
OT Prophecy NT Fulfillment
Zechariah 11:13b
"And the LORD said unto me, Cast it unto the potter: a goodly price that I was prised at of them. And I took the thirty pieces of silver, and cast them to the potter in the house of the LORD."
Matthew 27:6-7
"[6] And the chief priests took the silver pieces, and said, It is not lawful for to put them into the treasury, because it is the price of blood. [7] And they took counsel, and bought with them the potter's field, to bury strangers in."

Tanakh - Neviim - Zechariah 11:13b

"And HaShem said unto me: 'Cast it into the treasury, the goodly price that I was prized at of them.' And I took the thirty pieces of silver, and cast them into the treasury, in the house of HaShem."

Hebrew OT - Zechariah 11:13b

רשא רקיה רדא רצויה-לא והכילשה ילא הוהי רמאיו
תיב ותא ךילשאו ףסכה םישלש החקאו םהילעמ יתרקי
.רצויה-לא הוהי

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