Postfix smarthost with authentication
I used the relay host of my internet provider but this was causing issues since my email was getting mark as SPAM in gmail.
It was already on my to-do list to move my outgoing mail to my mail provider also to make it easier to move to another ISP or to implement SPF but was not on the top of my to-do list.
My email provider requires authentication, so I needed to reconfigure postfix in my FreeBSD mail jail to use a relay host with authentication.