Index: wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php
===================================================================
--- wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php	(revision 39258)
+++ wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php	(working copy)
@@ -708,7 +708,7 @@
 		$post = get_post( $request['id'] );
 
 		if ( $post && ! $this->check_delete_permission( $post ) ) {
-			return new WP_Error( 'rest_cannot_delete', __( 'Sorry, you are not allowed to delete posts.' ), array( 'status' => rest_authorization_required_code() ) );
+			return new WP_Error( 'rest_cannot_delete', __( 'Sorry, you are not allowed to delete this post.' ), array( 'status' => rest_authorization_required_code() ) );
 		}
 
 		return true;