[Footnote 62: WOOLSEY, _op. cit._, 94. _Cf._ on the survival of the principles of Roman law, GEFFCKEN, _op. cit._, 24, 25.] Accordingly, the legislation of the early Christian emperors shows no radical departure from the principles of the existing civil law. Divorce _ex consensu_ was not prohibited until Justinian, who decreed that only when both partners are about to enter the cloister shall a separation by mutual agreement be permitted.[63] But this prohibition was short-lived; for in consequence of it the number of suits growing out of "poisoning or other attempts upon life among married people increased in so frightful a manner"[64] that the provision was abrogated by Justin II., the immediate successor of Justinian.[65] On the other hand, the efforts of Constantine and later rulers are directed mainly toward checking the evils of one-sided divorce. This is done chiefly through restricting the number of legal grounds of separation and sharpening the penalties for their disregard. Thus in 331 Constantine ordains that trifling causes (_exquisitae causae_) shall no longer suffice for a _repudium justum_ or legal divorce at the will of one party. The woman may put away her husband only when he is a murderer, poisoner, or violator of sepulchers; and the man is allowed to repudiate his wife only when she is guilty of poisoning, procuring, or adultery. If the divorce takes place for any other reason, the woman so violating the statute shall forfeit all claim to restitution of dower and suffer transportation to an island; while the man in like case must at once surrender the entire _dos_, being prohibited also from contracting another marriage.[66] "Still further, if he thus married, his repudiated wife 'could invade his house,' as the law expresses it, and acquire possession of the entire dower of her successor."[67] It should be noted, however, that the Roman principle of divorce _bona gratia_, or one-sided separation for a legal cause not implying any guilt or offense, was still retained.[68] [Footnote 63: _Nov._, 117, c. 10.] [Footnote 64: GEFFCKEN, _op. cit._, 25.] [Footnote 65: _Nov._, 140; _cf._ GEFFCKEN, _loc. cit._] [Footnote 66: GEFFCKEN, _op. cit._, 25: _L. 1. C. Theod. de repud._, 3, 16. _Cf._ also WOOLSEY, _op. cit._, 96, 97. On the legislation of Constantine and his successors see WÄCHTER, _Ehescheidungen_, 201 ff., 259 ff.; GLASSON, _Le mariage civil et le divorce_, 203 ff.; ESMEIN, _Mélanges_, 157 ff.; LUCKOCK, _Hist. of Marriage_, 112 ff.; COMBIER, _Du divorce_, 81 ff.; TISSOT, _Le mariage_, 88 ff.; TEBBS, _Essay_, 139 ff.; BENNECKE, _Ehebruch_, 16 ff.; HENNET, _Du divorce_, 25 ff.; POPP, _Ehescheidung_, 62 ff.] [Footnote 67: WOOLSEY, _op. cit._, 97; WÄCHTER, _op. cit._, 207 ff.]