I don't know how to state it any more simply. Regarding one proposition as more likely than the other is not the same as believing that said proposition is true. This is one of the most fundamental concepts in any sort of critical thinking methodology, including science. As a juror, I can form the provisional opinion that it is more likely than not that a defendant committed the crime of which he is accused, yet have enough doubt that I cannot believe him to be guilty. If I used your logic as a juror, I would vote to convict a man who might be innocent.
Not true (re the highlighted), and that's why jurors are mandated to reach their opinion only on the basis of being "beyond all reasonable doubt".
On the overall claim that you are trying to make, you are wrong. If someone says that on balance, ie greater than 50-50, they believe something is true (eg the existence of Jesus). Then that is a statement of positive belief.
The fact that they may say that the belief is only very weakly held, and that they think it's only slightly less likely that the belief is untrue, does not change their decision of overall belief in the proposition. It only means that their qualifying remark expresses very considerable doubt about their expressed position of belief. But overall, their judgement is still one of saying they do believe the proposition is true.
If you said 50-50, then that would not be a belief expressed in either direction. That’s' a shorthand statement of saying you cannot decide whether the proposition is more likely to be true or less likely to be true - you think either position is equally likely.
But saying you are 60-40 in believing that Jesus was real, is literally, in proper use of English language, a statement expressing belief that Jesus was real. You could add the word
"probably" if you wanted to, and say
"Jesus was probably real", but that's actually an unnecessary/redundant elaboration, because the uncertainty expressed by the addition of that word
"probably" must always be present whether you state it or not, because there is literally no such thing as absolute certainty, ie there must always be room for some doubt in anything and everything.
So, in summary - if you say you believe 60-40 that Jesus was real, then it’s a statement saying you
do believe (overall) that Jesus was indeed real. The statement includes considerable room for doubt, as any meaningful statement always must (because 100% certainty is physically impossible, eg according to QM), but the statement overall is literally and precisely a statement saying that your conclusion is that he was real.