Paraphrase Against Interpretation

As said to an interlocutor:

....So, I don't think you've oversimplified anything. Rather, don't get a swelled head, you've vividly made your case. We're agreed, I think we are, that every paraphrase is an interpretation but not every interpretation is a paraphrase, even as I'd say some interpretations are paraphrases. 

Concise definitions of the two words are:

Paraphrase: ...to express the meaning of (the writer or speaker or something written or spoken) using different words, especially to achieve greater clarity...

Interpretation: ...the action of explaining the meaning of something...

So, express the meaning against explain the meaning. 

Another example plucked from the Internet:

This above all, to thine own self be true. 

Most important, be true to yourself. (paraphrase) 

Shakespeare believes that the most important loyalty a person can have is to his or her own self. (Interpretation) 

To go to the second example first, the distinction there seems to be without a difference, just a few more words to say the same thing. 

But in your example, your "explanation" includes an insight into the relation and connection between the energies of political revolution and the spiritedness of youth. This insight illuminates part of the meaning of those lines in at least two ways that their paraphrase can't reach: it elucidates implied meeting, which paraphrase in its nature doesn't; and it explains these lines' meaning contextually by drawing out their meaning as they relate to the rest of the poem, which paraphrase in its nature can't reach.

So, your example makes clear that once the core of interpretation as explanation is fixed, then the latitude of what can comprise it takes it when it's evident in those widths, lengths and depths beyond expression as the core of paraphrase. 

Btw, it strikes me that an insupportable interpretation makes that point too. An interpretation not at all justifiable by the text, astride from the text,  is still an interpretation. And when it's that it's a country mile from a paraphrase.

Seen so, their difference now turns out, to my mind, not to be that fuzzy even as they can overlap...