given, with the same appurtenances, for he confirms nothing by such general  [confirmation] except what was comprised in the gift. Hence if in the first gift  the advowson of the church was excepted, that general confirmation does not  include the advowson. As the thing given is transferred, so is it confirmed, for a  confirmation adds nothing to a gift nor does it detract from or diminish it.]1
A donor may impose a law and a condition on a gift.
 Thus a donor may change the causa possidendi of the thing in the donee without any  resumption or change of possession, but cannot transfer it from one person to another  without a change of possession.2 A gift may be simple, absolute and complete,  without condition or modus, [or] 3a donor may impose on his gift, with the consent of  the donee, a law, a condition or a modus, provided it is not to the prejudice of others,  though it may be to his own prejudice and that of his heirs and contrary to what the  law of the land and the custom of the realm [would ordinarily provide], 4 for an agreement  sometimes prevails over law.5 [It may be] of the whole, no part of the thing or  its appurtenances excepted,6 for one may give a thing and retain part of it, or of its  appurtenances, [so that] what was part [of the thing] or of the appurtenances ceases  immediately after the gift to be such with respect to the donee.78One may give all the  right he has in a thing, that is, the rights of possession and of property, to the donee  and his heirs, quit of himself and his heirs forever, a gift which is simple and absolute,  [or] to such gift, when it is first made, the donor may add the law and condition  that after a time the thing given revert to him, with the right of possession only, to  be held for his life, the proprietas remaining with the donee, or so that both rights, of  possession and property, remain with the donee and the usufruct revert after a  time to the donor, for a term of life or years. 9<One who has the proprietas only,  another having the possession, that is, the free tenement, may give what he has to  another, that is, the proprietas, saving to the tenant his free tenement and his right  of possession for life, so that after his death the possession revert to the proprietas.10  He who possesses ought here to be attorned, with respect to his service and the rest,  to him who has the property, just as he formerly was attorned to the donor.  Similarly, if one having both rights has granted the usufruct to another,