The word for today is – MORTGAGE – which comes from the Latin word – MORTUUS – which means – DEAD and the French word – GAGE – meaning – TO PLEDGE.
It means – to grant or convey, as property, for the security of a debt, or other engagement, upon a condition that if the debt or engagement shall be discharged according to the contract, the conveyance shall be void, otherwise, to become absolute, subject however, to the right of redemption.
In medieval England money would only be loaned to you if you had the ability to repay. If you were eventually going to inherit wealth from your father you could obtain a mortgage with the promise that you would repay the loan upon the death of your father from whom you would inherit the monies. Therefore you pledged to repay upon the death of your father.