Matthew 27:1-10 The thirty pieces of silver

                                                 Old Roman coin

27 When the morning was come, all the chief priests and elders of the people took counsel against Jesus to put him to death:

² And when they had bound him, they led him away, and delivered him to Pontius Pilate the governor.
³ Then Judas, which had betrayed him, when he saw that he was condemned, repented himself, and brought again the thirty pieces of silver to the chief priests and elders,
⁴ Saying, I have sinned in that I have betrayed the innocent blood. And they said, What is that to us? see thou to that.
⁵ And he cast down the pieces of silver in the temple, and departed, and went and hanged himself.
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.
⁸ Wherefore that field was called, The field of blood, unto this day.
⁹ Then was fulfilled that which was spoken by Jeremy the prophet, saying, And they took the thirty pieces of silver, the price of him that was valued, whom they of the children of Israel did value;
¹⁰ And gave them for the potter's field, as the Lord appointed me.
-Matthew 27:1-10 King James Version (KJV) 

Arcana Coelestia, by Emanuel Swedenborg, [1749-56], tr. by John F. Potts [1905-10], at sacred-texts.com 

2276. 

...the signification of the number thirty. That "thirty" signifies somewhat of combat, thus but a little of combat, comes from the fact that this number is compounded by the multiplication of five (by which is signified some little), and six (by which is signified labor or combat, as was shown in volume 1, n. 649, 720, 737, 900, 1709). [2] Hence also this number, wherever read in the Word, signifies something that is relatively little; as in... [3]  ...Matthew: They took the thirty pieces of silver, the price of Him whom they had bought from the sons of Israel, and gave them for the potter's field, as the Lord commanded me (Matt. 27:9-10); from which it is plainly evident that "thirty" here denotes the price of what is but little valued. The valuation of a servant who was held as being of little account, was thirty shekels; as is evident in Moses: If the ox gore a manservant, or a maidservant, he shall give unto their master thirty shekels of silver; and the ox shall be stoned (Exod. 21:32)... [5] So in other passages where "thirty" is named in the Word... In Mark also "thirty" denotes a little: The seed which fell into good ground yielded fruit growing up and increasing, and brought forth, one thirty, and another sixty, and another a hundred (Mark 4:8), where "thirty" denotes a small growth, and that which has labored but little. These numbers would not have been marked out for use, unless they had contained within them the things which they signify.