Hi @LKHHKL ,
When seeking to understand the meaning (or its differences) of the Bible or in fact any given text, it is best to read the whole context and see how the particular text you are struggling with to understand fit in to the whole context.
If it doesn’t change the context it is conveying, then I wouldn’t be too concerned with minor variations.
For example, when I have someone ask me whether he should translate a certain word as A or B in another language, to accurately answer the person, I would usually request for the context of how he plan to use the word first. Once he told me the context, then sometimes I find that both words, though different, could be synonymously used, without altering the meaning.
In the above context, Paul was simply commending his Roman readers of their well-known faith around the world in v.8 (back then commendable faith means they faced intense persecutions) and that in v.9 he was comforting them by letting them know that he was unceasingly praying for them, and the God, that Paul preached, was his witness (in other words, he was not lying about it).
I hope that helps you in your earnest desire to properly understand the integrity of the text you are studying.
Thanks @KLM for laying out the full text for us. so as to represent it accurately. I also love @jlyons ‘s humility in discussing this text.