The following 3 parameters will give you the posts in Ascending order from the date it was published *(i.e The older posts will be shown first)*
**'post_status' => 'publish', 'orderby' => 'publish_date', 'order' => 'ASC'**
When you change the *order* to *DESC* you will get the posts in Descending order from the date it was published *(i.e The latest posts will be shown first)*
**'post_status' => 'publish', 'orderby' => 'publish_date', 'order' => 'DESC'**
<?php
$postsPerPage = 10;
$page = 1;
?>
<?php
$query = new WP_Query(array(
'cat' => 4,
'post_status' => 'publish',
'orderby' => 'publish_date',
'order' => 'ASC',
'paged' => $page,
'posts_per_page' => $postsPerPage));
?>