Pope Benedict XVI's motu proprio, Summorum Pontificum, has changed the juridical situation of the Mass. Until recently, the traditional Mass was presented as being prohibited and allowed only under an indult, that is, a special, exceptional permission joined with special conditions.
The conditions attached to the celebration of the traditional Mass under the Indult were two-fold: the recognition of the orthodoxy and legitimacy of the New Mass and the acceptance of the Second Vatican Council's decisions and reforms.
Pope Benedict XVI changed the juridical situation of the Mass stating that the traditional Mass has never been abrogated. Thanks to this statement, the Mass has been reestablished as a universal law of the Church and can no longer be considered as prohibited or even as an exception: unfortunately, the expression "extraordinary form" used in the motu propio is misleading.
Nevertheless, the practical situation of the Mass, due to the attitude of the majority of the bishops has hardly changed from the previous state. Practically speaking, the bishops continue to limit the celebration of the traditional Mass by seeking to grant a permission which is no longer necessary, oftentimes in addition to other arbitrary conditions.
In other words, for the time being, there is in general hardly a difference from the previous situation with the Indult Mass, though in certain particular places there might be a better treatment for the Mass, the priests and the faithful. This obliges us to invite the faithful to the same prudence as before about attending the Indult Mass.
We hope that this situation will gradually change and that the reasons which oblige us today to be very restrictive will little by little disappear, in a process of gradually recovering the reality of the sacrifice, the reality of the priesthood and the whole Christian spirit. But for now this is only a wish and a dream, apart from some exceptions.
Here is a summary of the dangers to which the faithful might easily be exposed by imprudently attending the traditional Mass celebrated today under said circumstances:
In doubt, the faithful should ask their pastors for advice.