not be admitted, no matter what the reason;1 if he is repelled the assise of novel  disseisin is not available to him2 though he claims that he had no intention of  withdrawing from possession, [Supposition is here preferred to truth.] for since  he left freely, formally, and without compulsion, there is, to say the least, a very  strong presumption that he had no clear intention of returning,3 and anyone,  whether he had such or not, could claim that he had no intention of withdrawing  and so revoke what had been done. Thus whether he did or did not intend to  return the donee will act properly if he keeps him out of seisin. 4Conversely, whether  from the first he had the intention of returning or not, if on his return the donor  ejects the donee, who cannot at once re-eject him, the assise of novel disseisin lies for  him despite any exception of tenuous seisin.56And so when both have withdrawn,  livery having been made and no one being left in possession; if the donor at once  returns and puts himself in possession [and] the donee on his return cannot  immediately eject him, the assise lies for him.7 When the donor's8 seisin is  adjudicated9 by the assise, the donee's will be good in perpetuity and the gift  thenceforward deemed neither fictitious nor feigned; hence after10 that, the donee  may regrant the thing to the donor for life without raising suspicion. 11For it is of  value to possess whenever possession was begun with the consent of him to whom it  belongs,12 and it suffices that he once consented, all the other necessary elements of  a valid gift being present. 13And if the consent of him to whom the thing belongs is  secured after possession was begun, though there was no such consent at the  beginning, that will suffice and be of benefit to the possessor though it is ex post facto.  And so if one begins to possess with the consent of him to whom the thing belongs,  the fact that his consent did not afterwards continue does not prejudice the  possessor, for he once began to possess with his consent,14 as in the first case.
How possession once acquired may be lost.
 We have indicated above how and by what persons possession is acquired,15 and  how the donee ought to use it.16 Now we must explain how, once acquired, it  may be lost. It is clear that possession is lost in very much the same way that it  is gained. Acquired corpore and animo, it is not lost unless both [are lost], since  it may be retained by intention alone, as was said above.17 Hence [though] when  one who has natural possession and civil [transfers], by some
11-12. D. 126.96.36.199: Prodest autem possedisse quotiens
[ex] voluntate eius ad quem ea res pertinet possideri coeptum est;
13-14. Ibid. (continuing the above): sed et si postea voluntas accessit eius ad quem ea res pertinebat, tamen prodesse possessori debere, unde si quis coepit quidem ex voluntate eius ad quem ea res pertinet possidere, postea vero voluntas non perseverat, nihil nocet quia semel possideri coepit ex voluntate.