the_content () doesn’t display the full content of the page

Hi,
I want to show the content on the Posts page.

For the purpose, I have used the following code after the posts loop

global $post;
$page_for_posts_id = get_option('page_for_posts');
if ( $page_for_posts_id ) : 
    $post = get_page($page_for_posts_id);
    setup_postdata($post);
    ?>
    <div id="post-<?php the_ID(); ?>">
        <header>
        <!-- Hiding the H1 element here <h1><?php the_title(); ?></h1> --> 
        </header><!-- .entry-header -->
        <div>
            <?php the_content(); ?>
            <?php edit_post_link('Edit', '', '', $page_for_posts_id); ?>
        </div>
    </div>
    <?php
    rewind_posts();
endif;

As a result, the content is displayed, but it is not showing full.
For example, if there are 350 words in the content, then only first 50 words are displayed.

Could you guys help me a bit?