Leviticus 27:29-31

Young's Literal Translation

²⁹ `No devoted thing, which is devoted of man, is ransomed, it is surely put to death.

³⁰ And all tithe of the land, of the seed of the land, of the fruit of the tree, is Jehovah's -- holy to Jehovah.

³¹ `And if a man really redeem [any] of his tithe, its fifth he addeth to it.