IV. Why was it necessary that this hypostatical unioon should be effected?
The reasons which made it necessary that the mediator should be a true man, and perfectly righteous, and at the same time, true God, have been presented and explained under the 16th and 17th Questions of the Catechism, so that it is not necessary that we should here repeat them. For these reasons it was necessary that a personal union should be effected between the natures of the mediator, that he might at the same time be very man and very God, who might be able to restore and merit for us that righteousness and life which we have lost ; for had not these natures concurred and met together in the person of the Word, as above described, he could not have accomplished the work of our redemption