The two Codes possess, on the one hand, common norms, and on the other, their own special features, that render them mutually autonomous. It is however necessary that even in the particular norms there is sufficient concordance. Indeed, discrepancies would have a negative impact on pastoral practise, especially in cases in which it is necessary to regulate relations between subjects that belong respectively to the Latin Church and an Oriental Church.
The Pope remarked that this is particularly evident in our times, in which the mobility of the population has resulted in the presence of a significant number of Oriental faithful in Latin territories. This new situation generates numerous pastoral and juridical questions, which demand to be resolved by means of appropriate norms.
For example, it should be recalled that Oriental faithful are obliged to observe their own rite wherever they may be and, as a consequence, the competent ecclesiastical authority has the grave responsibility of offering them adequate means to comply with such an obligation. Legislative harmonisation is certainly one of the means able to contribute to promoting the development of the venerable Oriental rites, permitting the sui iuris Churches the most effective pastoral action.
However, it is necessary to keep in mind the need to recognise the disciplinary particularities of the territorial context in which the inter-ecclesial relations occur. In the west, prevalently Latin, the correct balance must be found between the protection of the rights of the Oriental minority and respect for the historical canonical tradition of the Latin majority, so as to avoid undue interference and conflicts and to promote fruitful collaboration between all the Catholic communities present in a given territory.
A further reason for integrating the legislation of the Code of Canon Law with explicit provisions parallel to those existing in the Code of Canons of the Oriental Churches is the need to clarify relations with faithful belonging to the non-Catholic Oriental Churches, now present in a more significant number in the Latin territories.
Finally, it should be shown that also canonical doctrine has allowed some discrepancies between the two Codes to be noted, indicating with substantial convergence the problematic points and how to make them concordant.
The aim of the provisions introduced by the present Motu Proprio is to arrive at a harmonious discipline that offers certainty in the method of pastoral action in concrete cases.
The Pontifical Council for Legislative Texts, by means of a Commission of experts in oriental and Latin canon law, has identified the issues most in need of normative adjustment, and has drawn up a text sent to around thirty Consultors and experts throughout the world, as well as to the Authorities of the Latin Ordinariates for oriental faithful. Following an appraisal of the observations thus gathered, the Plenary Session of the Pontifical Council for Legislative Texts approved a new text.