In matrimony, is the very essence of the contract. It can be given only by a person who is not legally hindered from giving it; it must be voluntary, without a degree of compulsion that would prevent the exercise of free-will; it must be muiual, given not by one but by two; and it must signify that the parties take each other then and there (not conditionally, nor at some future time), with the intention of living together as husband and wife until death shall part them.