Ronaldo was filmed saying "bismillah" while taking the penalty at Portugal as well. Saudi Arabia is really rubbing off on him and he seems to be enjoying life there, he scored goals as well for the national team and I am sure that when he comes back he will keep scoring again for his team as well.
It could be a respect made by him toward all of muslims in saudi. Ronaldo will not ask nassr to extend his contract if he was not feeling good by playing there. It was showing if he is now feeling so confidence to play in that club.
It's also proving that if saudi pro league is not that bad like what people thought before. Ronaldo is enyjoying his life there. He can earn good amounts of money and various facilities from the club. No doubt if he is feeling better.
Messi has been also taking the wrong choice by moving to the MLS instead of SPL.
The thing is, dude is very very expensive for them, but he is also bringing success and fame to them as well, he was a player that was bigger than the club when he came in and I am sure that he is still like that, I mean if you look at it from some personal perspective. That is something to care about and think about when making a transfer. Him being basically a spokesperson for the entire league? That wasn't even assumed and it is going that way very easily at this point.
Ronaldo is just showing how great his attitude, even though if he has different religion but he is still putting all of his respects to the moeslim. Ronaldo was playing at saudi pro league which is also majority of of its supporters were muslims.
Im not even feeling surprised to see him does it but he deserves some praises.