I actually took a whole class in college on syncretic Christianity, and we had a unit on Goa, and there are Catholic shrines in Goa that are also frequented by Hindus, and you can find people there who identify as Christian but say that Vishnu is their favorite saint, and people who identify as Hindu who say that Jesus is their favorite god.

For central authorities of the Catholic Church, and Hindu theologians, this is all heretical, but the Catholic Church allowed for flexibility around traditions as it expanded. One big example is that many of what are considered Christmas traditions in northern Europe (the Christmas tree being an especially prominent one) are hangovers from traditions that predate Christianity.