A very good question which I can only answer by opinion. I take the view that the Christians in the play are a thoroughly unattractive lot who only use a veneer of Christianity to cover their essentially nasty commercial instincts. The most obvious expression of Christianity is Portia's 'quality of mercy' speech but mercy is totally absent when she is giving her judgement against Shylock. Not only does he lose the case but he loses everything to Antonio and the Venetian state and is an absolutely broken man at the end of the trial. And what has he done wrong? His attempted revenge against Antonio for his admitted insults may be unpleasant but Antonio has entered freely into the bond and only semantic tricks get him out of it.
The part of the play following the trial shows the Christians at their most unpleasant. They return triumphantly to their hedonistic ways with not a thought for the man they have ruined. Even his daughter thinks no more about him as they indulge in their silly games with all sorts of sexual innuendo thrown in to underline their unpleasantness. To me Venice is a commercial state writ large with Christian values very much a shallow hypocrisy.
During Venice's phase as a powerful European city-state, its religion was Roman Catholic. If you visit Venice today, you will still see the beautiful and magnificent Palazzo Ducale (the palace where the rulers of Venice lived) right next door to the beautiful and magnificent Basilica di San Marco, Venice's ancient cathedral. The two buildings dominate the centre of Venice in St Mark's Square. The Church and The State always try to work hand-in-hand to support each other's existence. So your answer is probably 'both'.
Footnote Example: When Venice launched a religious crusade to recapture Jerusalem from the muslims in 1203, they were tempted from their mission by the immense wealth of poorly-defended Constantinople. They raided there instead with immense brutality, slaughtering tens of thousands of fellow Christians in order to steal the vast treasures of ancient The Roman Empire. It has been often described as one of the most profitable and disgraceful sacks of a city in history. The Venetians forgot about Jerusalem completely and came home drenched in blood and gold. You can still see the stolen horse and chariot, which had stood in the centre of Constantinople since antiquity, proundly displated on top of the Cathedral in St Mark's Square in Venice. It seems the Venetian Church was happy to display profit from business, no matter how that profit was made.