In 1980 the Catholic Book Publishing Company released a book entitled the New St. Joseph People’s Prayer Book. It is one of their largest comprehensive collections of prayers ever produced, including not only traditional and official prayers from the Catholic faith tradition and liturgy, but prayers from other faiths, including Islam.
In chapter 5, Prayers from Other Religions, there is a “Prayer to Walk Uprightly Before God,” the “Prayer of the 99 Names of God,” the “Prayer for Obedience to God,” and another in “Praise of the Ineffable God,” all traditional Muslim prayers. All the prayers in the book can be said by Catholics, and the book has a Nihil Obstat and Imprimatur.
As a Roman Catholic from a Jewish background I understand a little of where you are coming from. Fellow Catholics can get really squeamish when they learn that you might worship in ways that they never knew have approval from the Church. It is best to be patient with others as these details of the faith are generally unknown and left unapplied except in the case of a minority from a different culture.
Conversion to the Catholic faith does not mean we are forced to assimilate. Mexican Catholics are allowed to continue to celebrate Dia de los muertos and are allowed to create ofrendas (a table of offerings to the dead) every November and have been doing this for generations. Irish Catholics have been allowed their ghostly customs of Halloween. Several Christmas customs in some lands come from non-Christian cultural observances. These things are accepted without a blinking of the eye by Catholics. But do something associated with an Eastern land where Jews and Muslims live and suddenly you might hear, “Oh no! You can’t do that!” Be patient when that happens.
The world is shrinking faster than most can keep up with. And there is a lot to the faith that we often don’t know exists. The unknown makes people fearful. And when people sometimes tell you “no you can’t” when they don’t really have all the facts straight, remind yourself that even their mistakes show they just have our best interests at heart and are trying to protect us from what they (mistakenly) believe can be harmful.
And while 1 Corinthians 9:19-23 can be applied here in regards to you and others who know where you come from, don’t forget Romans 14:22: “The faith which you have, have as your own conviction before God. Happy is he who does not condemn himself in what he approves.”