score:2
Ask your priest. There are a lot of good reasons for attending non-Catholic religious ceremonies and Islamic ones are no exception. Your key concern-- whether or not the actions you are considering would constitute communicatio in sacris-- is the correct key concern to have, but it is well possible that what you are contemplating either will not in fact constitute such a sin, or, if it does, that you can arrive at some other possible course of action by discussion with your priest that both satisfies your good desire to 'sing a new song unto the Lord' and avoids the problem of false communion. It is certainly the case that attending non-Catholic prayer service and, separately, praying with non-Catholics have been approved by the Church in special circumstances numerous times in the past. Furthermore, the adoption of non-Catholic prayers to Catholic purpose is as old as the Church itself and speaks to the universality of human regard for the One True God. Because the exact circumstances are so important and because you likely should receive pastoral advice as to how to go about doing this, I think as a Catholic you need to talk with a priest. But if your priest approves of this course of action than you're definitely good to go!
Although it does not directly concern you, be aware that this is one of the situations where your priest is advised to request the action of a Bishop on the matter provided the situation is sufficiently unprecedented:
- The ecumenical movement seeks to be obedient to the Word of God, to the promptings of the Holy Spirit and to the authority of those whose ministry it is to ensure that the Church remains faithful to that apostolic Tradition in which the Word of God and the gifts of the Spirit are received. What is being sought is the communion that is at the heart of the mystery of the Church, and for this reason there is a particular need for the apostolic ministry of Bishops in the area of ecumenical activity. The situations being dealt with in ecumenism are often unprecedented, and vary from place to place and time to time. The initiatives of the faithful in the ecumenical domain are to be encouraged. But there is need for constant and careful discernment by those who have ultimate responsibility for the doctrine and the discipline of the Church.48 It belongs to them to encourage responsible initiatives and to ensure that they are carried out according to Catholic principles of ecumenism. They must reassure those who may be discouraged by difficulties and moderate the imprudent generosity of those who do not give sufficiently serious consideration to the real difficulties in the way of reunion. The Pontifical Council for Promoting Christian Unity, whose role and responsibility it is to provide direction and advice on ecumenical activity, offers the same service to the whole Church.
(from here)
Upvote:6
It is forbidden for Catholics to engage in communicatio in sacris—joining non-Catholics in their false worship or prayer, e.g., worshiping Islam's false god Allah, who is not the Holy Trinity:
1917 Canon 1258 §1 It is not licit for the faithful by any manner to assist actively or to have a part in the sacred [rites] of non-Catholics.
cf. Dom Augustine's A Commentary on the New Code of Canon Law on '17 Can. 1258
This law is expressed in the 1983 code, in the section "Delicts against religion and the unity of the Church," as:
1983 Can. 1365 A person guilty of prohibited participation in sacred rites (communicatio in sacris) is to be punished with a just penalty.
Upvote:6
According to the tafsīr (commentary) of Ibn Kathir, a Muslim Qurʿānic commentator, the phrase وَلَا الضَّالِّينَ (walā ḍ-ḍāllīna)—“nor of those who go astray,” refers to the Christians.
Allah asserted that the two paths He described here are both misguided when He repeated the negation 'not'. These two paths are the paths of the Christians and Jews, a fact that the believer should beware of so that he avoids them. The path of the believers is knowledge of the truth and abiding by it. In comparison, the Jews abandoned practicing the religion, while the Christians lost the true knowledge. This is why `anger' descended upon the Jews, while being described as 'led astray' is more appropriate of the Christians. Those who know, but avoid implementing the truth, deserve the anger, unlike those who are ignorant. The Christians want to seek the true knowledge, but are unable to find it because they did not seek it from its proper resources.
Therefore, by reciting Salah, which is found in Sūratu l-Fātiḥa, the initial surah of the Qurʿān, a Christian would in fact be denouncing the truthfulness of Christianity and affirming the truthfulness of the Qurʿān. This has severe implications, including denouncing the crucifixion of the Lord Jesus Christ, his resurrection, and his ascension, all of which are denied in the Qurʿān.