Correct Translation
The text of the Graduale Romanum has not been changed as far as the music is concerned. In the interest of their being more readily understood, however, the responsorial psalm (which St. Augustine and St. Leo the Great often mention) as well as the entrance and communion antiphons have been revised for use in Masses that are not sung.
After what we have presented concerning the new Roman Missal, we wish in conclusion to insist on one point in particular and to make it have its effect. When he promulgated the editio princeps of the Roman Missal, our predecessor St. Pius V offered it to the people of Christ as the instrument of liturgical unity and the expression of a pure and reverent worship in the Church. Even though, in virtue of the decree of the Second Vatican Council, we have accepted into the new Roman Missal lawful variations and adaptations,[15] our own expectation in no way differs from that of our predecessor. It is that the faithful will receive the new Missal as a help toward witnessing and strengthening their unity with one another; that through the new Missal one and the same prayer in a great diversity of languages will ascend, more fragrant than any incense, to our heavenly Father, through our High Priest, Jesus Christ, in the Holy Spirit
Original from the Pope
Quod reliquum est, licet textus Gradualis Romani, ad cantum saltem quod attinet, nοn fuerit mutatus, tamen, facilioris intellectus gratia, sive Psalmus ille Responsorius, de quο S. Augustinus et S. Leo Magnus saepe commermorant, sive Antiphonae ad Introitum et ad Communionem in Missis lectis adhibendae, pro opportunitate, instaurata sunt.
Ad extremum, ex iis quae hactenus de novo Missali Romano exposuimus quiddam nunc cogere et efficere placet. Cum Decessor Noster S. Pius V principem Missalis Romani editionem promulgavit, illud veluti quoddam unitatis liturgicae instrumentum idemque tamquam genuini religiοsique cultus in Ecclesia monumentum christiano populo repraesentavit. Haud secus Nos, etsi, de praescripto Concilii Vaticani II, in novum Missale legitimas varietates et aptationes (Cf CONCILIUM OECUMENICUM VATICANUM II, Const. de sacra liturgia Sacrosanctum Concilium, nn. 38-40; AAS 56, 1964, p. 110) ascivimus, nihilo tamen secius fore confidimus, ut hoc ipsum a christifidelibus quasi subsidium ad mutuam omnium unitatem testandam confirmandamque accipiatur, utpote cuius ope, in tot varietate linguarum, una eademque cunctorum precatio ad caelestem Patrem, per summum Pontificem nostrum Iesum Christum, in Spiritu Sancto, quovis ture fragrantior ascendat.
Erroneous Translation
Even though the text of the Roman Gradual, at least that which concerns the singing, has not been changed, still, for a better understanding, the responsorial psalm, which St. Augustine and St. Leo the Great often mention, has been restored, and the Introit and Communion antiphons have been adapted for read Masses.
In conclusion, we wish to give the force of law to all that we have set forth concerning the new Roman Missal. In promulgating the official edition of the Roman Missal, Our predecessor, St. Pius V, presented it as an instrument of liturgical unity and as a witness to the purity of the worship the Church. While leaving room in the new Missal, according to the order of the Second Vatican Council, "for legitimate variations and adaptations,"(15) we hope nevertheless that the Missal will be received by the faithful as an instrument which bears witness to and which affirms the common unity of all. Thus, in the great diversity of languages, one unique prayer will rise as an acceptable offering to our Father in heaven, through our High-Priest Jesus Christ, in the Holy Spirit.