Learning a new programming language is nowhere near as hard as learning a new human language. That's true even if it's a different paradigm but especially when you're talking about languages which have similar paradigms. The real slayer in picking up a new language is that the list of vocabulary you need to learn is endless.

You can be writing a program in a new language that may not be totally idiomatic but works in a few days. You can't carry on a conversation in a new language that fast.