Change password on user profile (customer account in Craft Commerce)
Commerce just relies on existing Craft functionality for this and if you look at UsersController->saveUser, you can see that if the existing password is incorrect, then the error will be added to the UserModel's currentPassword property.

So something like this should work:

&lt;ul&gt;
    {% for error in user.getErrors('currentPassword') %}
        &lt;li&gt;{{ error }}&lt;/li&gt;
    {% endfor %}
&lt;/ul&gt;