Just a few words to the above good and practical suggestions - ’ The Everlasting Man ’ by G.K Chesterton , if I remember right, gives a good and concise approach to the diffrences between the faiths and hope there are others - The Word itself can be the best , when read with prayerful discernment - the friend migt even appreciate the suggestion to read the The Word in the Eucharistic presence .
Catholicism requires a good degree of faith and trust in and from a personal relationship with an all holy and loving God , whose love and goodness alone is the reason for the incarnation and where personal suffering, when accepted and surrenderd /united to The One who sufferred in the power of love , to give strenght and hope to His children from the trust they can palce in Him can even bring joy in sufferings ; hindu mythologies may be come close , yet often errr and thus makes it may be more confusing unless one can use the latter to discern the errors and lies and thus to uphold and appreciate the real TRUTH .
As to the reasons why most of India is still hindu, unsure as to the main reasons - one word that comes to mind is - ’ the light came into the world but men preferred darkness ’ ; faiths that seem to give the appearance of control to man , that ’ good works’ alone would merit heaven automatically , may be gives the false sense of autonomy without the difficult process of conversion to a good , loving , forgiving heart that recognise man’s sinfulness and nothingness at one level, yet man’s supreme role and worth, as a child of God who has the need to accept that role from His mercy . True , hinduism , to the best of my limited knowldge of it , does hint at some of these -yet does not bring out the truth of the total , selfgiving Father love which is the truth revealed in our Lord .
The reason for the lack of conversions might even have something to do with the errors of the( hindu) cast mentality that crept into the Church in earlier times and sort of either did not encourage or even discouraged conversion of the ’ lower casts ’ - for there was a time in the not distant past, when many Christian households had sizable #s persons who worked as field hands and such ( similar to the negligence in not actvely taking efforts to convert persons of similar backgrounds in U.S .!)
Similarly, while the church did do much to educate persons of all backgrounds , to help them to earn a living, unsure if similar zeal was given to give them the real truth that would have affected them at far reaching realms !
Interestingly,as far as I know, it was with the coming of the Latin missionaries that the missionary role of the SyroMalbar Church got a real boost and since then she has done admiringly well - to have become a vibrant missionary Church.
May God have mercy , esp. as the Church in India faces increasing restrictions on conversions and baptisms .
May the yearning to see The Face of The Father that stirs in every heart be richly fulfilled , by The Church that alonce can do the same to the best !
You should know better than that. :tsktsk:
Peace
I am a Brahmin convert to Catholicism. Go easy on your friend. Do not be imposing, but steadily introduce him to the Church; starting with the basics: The rosary, communion of saints and the Eucharist. As Blade and Blood suggested, it would also help if you studied on Brahminism (not Hinduism - there is alot of difference as you will find out later). Take notes of your study in Brahminism and compare similarities with Catholicism or even Judaism. Relate them to him only when he asks questions about the Church. Better yet, ask him to join this forum and myself and the others here can help him with his journey. 
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