I'm sorry, I don't understand.  What is the "it" that doesn't make what clear?  The statement that you have kept deleting says that Trent reaffirmed (affirmed again) the then existing teaching that Christian marriage is a sacrament.  The statement does make that clear.  If you want to insert a statement that marriage (like the other sacraments) was not always recognized as a sacrament, find a reliable source that says so and insert it at an appropriate point.  That appropriate point is obviously not the time of Trent, since by then marriage was not only generally recognized in the Church as a sacrament but had even been several times dogmatically declared to be such.  You'd also have to explain the significance you think you see in the fact that in this respect marriage is in no way different from the other sacraments, none of which was or could be recognized as a sacrament until a theology of sacraments was developed.  Isn't that obvious?
As for the latest edit, which said that the Council of Trent reaffirmed the existing teaching only "from their perspective", that is an utterly silly, unsourced, imaginative addition that contrasts with the clear decisive statement of the Fathers of the Council, who certainly wouldn't have dreamt of adding phrases such as "from our perspective" to their clear reaffirmation of the existing teaching!  The edit was no more than wishful-thinking violation of the "no original research" rule.  Rather, the word "research" in no way applies to this edit.