it ought not, because the obligation still continues between the heirs of the first  tenant and those of the sub-tenant, nor are the latter deprived by disuse since they  would have used if they could.1 Thus by special agreement one may renounce  matters introduced for his own protection and that of his people,2 who  derive their cause and origin from him. 3One may renounce matters introduced  for the benefit of himself and his own, contrary to common right, but by the same  token he cannot renounce matters introduced for the benefit of others, to their  prejudice, for that would be a wrong to them since they do not wish it [though]  not wrongful to him since he does,4 though contrary to common right. For to one  who knows and consents no injuria is done,5 and it is said who knows and  consents, because he who errs does not consent.67Suppose that one makes a gift  in these words, to hold to such a one and his heirs or to whom he wishes to give  or devise. At first sight it seems that the word devise is without effect and must  be disregarded, since a lay fee, unless it lies in special lands, as in burgages, cannot  be devised. Hence if a fee of that kind is sought in a testamentary action in a  secular court the legatee cannot be heard, for a testamentary action is not a matter  treated in such a court but one specifically excepted from being considered. And  if such a fee is sought in an ecclesiastical court, there a royal prohibition will bar  the legatee,8 and thus it is evident that in whichever court he sues an action will  fail him, [that is], when he is out of possession. But if he is in possession by virtue of  the devise and the heir claims by assise of mortdancestor, quaere whether the demandant's  action may be destroyed by the exception of gift by way of devise, since  [the heir's] ancestor, the testator, so intended, though contrary to common right.  I answer: it is submitted that this addition ought not to permit him to devise,  since a devise is a gift mortis causa and is simply confirmed by death, a gift9inter vivos  by livery. If it is to take effect as a gift inter vivos, livery must follow in the life of the  donor; if mortis causa, livery follows after death. But if there is no livery before death  a gift inter vivos will not be valid, any more than would an assignment.10 If livery  is made after death, as though it were a devise, [but] by force of a modus added to the  gift, as though it were a gift inter vivos, it will not be good as a gift inter vivos because  not followed by livery in the life [of the donor] nor as a devise because it is not a pure  devise, [the words] being an addition or supplement to a gift inter vivos. Hence it  ought to be valid under neither rationale, neither as a gift nor as a devise, and since  no action would be available to the donee if he were out of seisin, and properly so,  no exception against the assise of mortdancestor will lie for him when he is in seisin.11
How one ought to use his seisin.
 After possession has been acquired, though the donee at once has a