The National Catholic Register has an excellent piece by John Rist, Ph.D. an expert in ancient philosophy, patristics and moral philosophy.
In his piece, he decimates the spurious notion, put forth by Cardinal Kasper, that the ancient Church was much more relaxed and accepting of those who divorced and remarried.
I recommend you read the whole thing as it is not terribly long or abstract and hits right at the heart of the matter. A snippet...
Though others have put forward “early” — though non-existent — evidence for his position, the cardinal wisely offers nothing from the 150-odd years of Christianity, presumably accepting that marriage rules were then still strict and apostolically based. The first text he cites, from the mid-third century, is Origen (Commentary on Matthew 14:23-24) reporting that bishops of certain local churches “not without reason” allow Communion to those divorced-and-remarried. Yet Origen also says — not once but three times — that this practice is contrary to the Scriptures: hardly endorsement, nor even toleration from so biblical a theologian! Councils apart (I shall come to them), Cardinal Kasper offers further evidence only from the fourth century, observing that Basil (letters 188 and 199), Gregory of Nazienzen (Oratio 37) and Augustine are aware of the same practice occurring; what he omits to notice is that there is no indication of any of them concurring in what plainly contravenes their ordinary teaching.
Moving beyond “private” theologians, Cardinal Kasper claims that a more pastoral attitude is evidenced by the Council of Nicaea (325) – presumably by Canon 8 which (so he and others tell us) “confirmed” the more relaxed approach. Though this has occasionally been read into the text, yet its virtually certain intent is to permit Communion not to the divorced-and-remarried but to the widowed-and-remarried; for we need to bear in mind that a Christian’s marrying twice in any circumstances — including widowhood — was much debated, giving reason for the Council to address this uncertainty. Nor is Cardinal Kasper’s case strengthened by misapplying the Pauline notion of metanoia and going on to presume that the Fathers would consider “repentance” of the failure of a first marriage to justify entering into a second.
Read more: http://www.ncregister.com/daily-news/remarriage-divorce-and-communion-patristic-light-on-a-recent-problem#When:2014-04-2#ixzz2xkGG8Ky1