There is a distinct difference in preaching the Gospel to the pagans and mixing your own beliefs with theirs...something God does detest and He has warned His people against since the beginning of time...
“You cannot be partaking of ‘the table of Jehovah’ and the table of demons.”—
1 Cor. 10:21
“‘Separate yourselves,’ says Jehovah, ‘and quit touching the unclean thing’; ‘and I will take you in.’”—
2 Cor. 6:17
"But they mingled with the nations
And adopted their ways.
They kept serving their idols,
And these became a snare to them."
Psalm 106:35, 36