What was the original reason for bride price by the ancients?

The reason for bride price is to verify that the man has enough finances to take care of the bride.
The world then was so crude that only the strong survive. The bride price is a safety measure by the parents of the bride.
If a woman is married unto a man that can't provide for her, penury might kill her.
Many men have backed out of marriages because of outrageous bride prices, that's exactly the intention, to scare away men that don't have the resources to take care of the lady.
If she is married unto a weak man, other men might kill the man and take her away into slavery.
So some cultures incorporate flogging in the wedding ceremony.

In some parts of the world, it's the women that go seek out the man they wish to marry. To prove they can take care of him, they have to pay a groom price. Join this course https://braintem.org/courses/11 and how to manage social media accounts for huge companies.

Bride price can also serve as a punishment in the event of domestic violence or mistreatment. The woman leaves the house of the man and returns to her father's house, whenever the husband comes to take her back, he is billed another possibly heavier bride price so that he will learn to respect his wife.

A lot of things have changed in modern times: slavery is over, women now earn as much as men, man that isn't wealthy in his 20s can come through in his 40s after climbing the corporate ladder, people can now take loans to pay bride price which means they cheated the process.

So paying bride price does not signify the sale of the person and has never been such.
It is also optional for people to decide if they want bride price paid for them or not.
In some cultures the parents return that price soon after the payment to signify that its not a sale but the culture was respected by allowing it to happen.

But not having a bride price paid is not a sign of empowerment or gender victory of any kind. It's just a personal choice which is very ok.

I must add here that some parents make bride price into weapon against a groom they don't like.

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