How to display page/post content in WordPress theme

This case is relevant for cases when you need to display all the content of a particular page in a template. Below is an example PHP include for implementation.

<?php
$post1 = get_post( 100500 );
$text = $post1->post_content; // post content
echo apply_filters('the_content', $text); // output content
?>

Instead of 100500, you need to add the ID of your post/page, the content of which you want to display in the theme.