"I and Francis Mancias are now living amongst the Christians of Comorin. They are very numerous, and increase largely every day. When I first came, I asked them if they knew anything about our Lord Jesus Christ; but when I came to the points of faith in detail and asked them what they thought of them, and what more they believed now than when they were Infidels, they only replied that they were Christians, but that as they are ignorant of Portuguese, they know nothing of the precepts and mysteries of our holy religion. We could not understand one another, as I spoke Castilian and they Malabar; so I picked out the most intelligent and well-read of them, and then sought out with the greatest diligence men who knew both languages."
St. Francis goes on to say,
"After explaining the Creed I go on to the Commandments, teaching them that the Christian law is contained in those ten precepts, and that every one who observes them all faithfully is a good and true Christian and is certain of eternal salvation, and that, on the other hand, whoever neglects a single one of them is a bad Christian, and will be cast into hell unless he is truly penitent for his sin. Converts and heathen alike are astonished at all this, which shows them the holiness of the Christian law, its perfect consistency with itself, and its agreement with reason."
Saint Francis Xavier
Letter (to Superiors in Rome)