I may have asked this already, but how do I know it isn't saying, "The young man steps and walks onto the water?" As neither sentence sounds particularly typical in English, how do I know only one verb applies to the noun and not both?
Szerintem: Since lép comes directly after vízre we can assume it's step onto the water. Sétál could also be linked to vízre but it would be redundant to say in English: steps onto the water and walks onto the water. Therefore: steps onto the water and walks is most natural in English.
Onto the water makes no sense unless we are talking about Jesus or the kindergarten teacher again!! As far as I know into makes much more logical sense.
This is another example where "re" is translated literally to "onto," when in English, "into" would make much more sense. I've seen this several times. I admit it did give me a laugh, though.
I think in this case it was meant to mean "onto".
But I agree with you. I just had the opposite case 5 min ago, where it is "into" in Hungarian and "onto" in English.