Reply To: Modifying Comments.php in Frontier Child-Theme

This would be placed on the child-theme’s functions.php
Example:

function ra_comment_form_defaults( $defaults ) {
     $defaults['comment_notes_before'] = 'Warning! Spamming is against the law.';
     return $defaults;
}
add_filter( 'comment_form_defaults', 'ra_comment_form_defaults' );

For the code above to work, you have to remove any modifications to the original comments.php if there are any. The function that calls the comment form must simply be <?php comment_form(); ?>