Give it a try.
Here’s one possible solution:
<BOUCLE_rubrique(RUBRIQUES){id_rubrique}>
<h1>#TITRE</h1>
<BOUCLE_article(ARTICLES){id_rubrique}{par date}{inverse}{0,10}>
<a href="#URL_ARTICLE">#TITRE</a><br>
</BOUCLE_article>
#TEXTE
</BOUCLE_rubrique>
We call the page with the URL http://yoursite.net/spip.php?page=tutorial&id_rubrique=1
So, what’s happening here?
Our ARTICLES loop is integrated inside a RUBRIQUES (section) loop. The ARTICLES loop’s context is the id_rubrique generated by the RUBRIQUES loop, which will itself have the context given by the URL (id_rubrique=1). Therefore we are at the ARTICLES level, within the requested id_rubrique. At this point nothing has changed.
However, the RUBRIQUES loop allows SPIP to select the field values for the section in question: we can thus display the section’s #TITRE and #TEXTE. Note that this instance of #TEXTE would be that of the section even if we were also to call the article’s #TEXTE within the ARTICLES loop. The display function of SPIP guarantees that #TEXTE of an article does not interfere with identically named tags in the outer loop.