The music will probably be contemporary (they could be old fashion though but I wouldn’t know what that would look like or sound like in an Hispanic church). .
Depends. In my experience, a lot of Pentecostal churches are accepting of a “come as you are” dress code (as long as it is modest). Certainly, there are churches that will probably encourage “Sunday best” but there are also churches where you could wear jeans and flip flops on Sundays (I know I do).
If you are going to a church that adheres to old time “holiness codes” (somehow I don’t believe you are since the music is contemporary) but in any case if you are then you might want to dress formally (and if you are a woman avoid wearing pants and conspicuous jewelry).
However, whatever the dress code is since your a visitor the most that would be expected is that you dress modestly. I don’t think you could go wrong with business casual.
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