From Chabad.org: This section discusses various endowments pledged to the Temple coffers. A person can pledge the worth of an individual, in which case the Torah prescribes how much the person must pay — depending on the gender and age of the individual who is being “assessed.” An animal which is pledged to the Temple must be offered on the altar if it is fit for sacrifice — otherwise it must be “redeemed” for its value. If the owner chooses to redeem it, he must add one fifth of its value to the redemption price. The same rule applies to a house which is pledged to the Temple.
The most intriguing Passuk is in the beginning of this Aliya (3), saying that “Erkecha”, “your value” for pledging a man shall be… and so on. If the Torah is setting generic levels of value, it would make more sense to leave out the word “your” from the value, since it’s now everyone else’s value as well. Rashi is perplexed by this. The truth is that once you make a pledge of a certain value, the responsibility of paying that amount is now yours. Essentially, you’ve taken the value of this person, and made it yours, or your responsibility. Even if the value of the object or person now diminishes, you are still responsible for the amount originally pledged. It’s interesting that with one word, the Torah empowers the transfer of responsibility from the object to the person pledging the object. Maybe this is where the phrase “it’s all you” got started.