Implementing Revolution Slider The slider requires an unique ID per slide, wrapped in &lt;li&gt; tags, so I am trying this:

&lt;div id="rev_slider_15_1" class="rev_slider fullwidthabanner" style="display:none;" data-version="5.2.5.4"&gt;
&lt;ul&gt;

    &lt;!-- SLIDES --&gt;

    {% for testimonials in craft.entries.section('testimonials').limit(3) %} 

    &lt;li data-index="rs-{{ testimonials.id }}" &gt;

        &lt;!-- LAYERS --&gt;

        &lt;!-- LAYER NR. 1 --&gt;

        &lt;p class="tp-caption tp-resizeme" 
           id="slide-{{ testimonials.id }}-layer-2"&gt;

            {{ testimonials.body_testimonial }}

        &lt;/p&gt;

        &lt;!-- LAYER NR. 2 --&gt;

        &lt;span class="tp-caption tp-resizeme author" 
              id="slide-{{ testimonials.id }}-layer-3" &gt;

            {{ testimonials.title }}

        &lt;/span&gt;

    &lt;/li&gt;

    {% endfor %}    

&lt;/ul&gt;
&lt;/div&gt;


This results in the first slide entry with both Title &amp; Body, but the second and third slides only parse the Title not the Body.

Could someone verify the craft code is correct? The entries are made in a Channel section with a handle; testimonials.
Yes, your code looks fine.

It's possible that the second and third entries just don't have content in the body_testimonial field.

(Unrelated — I recommend using testimonial as your loop variable, since it represents a single Testimonial entry. This is a good practice in general: Variables that represent a list should have a plural name, and variables that represent a single object should have a singular name.)