On a profile, the Timeline lists that profile's activity, with profile_id. Leave profile_id out to list everyone's:
{jrCore_list module="jrAction" order_by="_item_id numerical_desc" pagebreak="20" page=$_post.p pager=true}Without a template, the Timeline module's own list template is used, so it looks like the profile timeline.
On a Site Builder page, an Item List widget with the module Timeline does the same without code.
See {jrCore_list}.