'Thirty' in the Bible

And some, falling on good earth, gave fruit, some a hundred, some sixty, some thirty times as much.

And the seed which was put in good earth, this is he who gives ear to the word, and gets the sense of it; who gives fruit, some a hundred, some sixty, some thirty times as much.

What will you give me, if I give him up to you? And the price was fixed at thirty bits of silver.

Then Judas, who was false to him, seeing that he was to be put to death, in his regret took back the thirty bits of silver to the chief priests and those in authority,

Then came true that which was said by Jeremiah the prophet, And they took the thirty bits of silver, the price of him who was valued by the children of Israel;