How to enter passphrase only once when operating in the terminal with ssh on macOS

If you only want to enter in your passphrase once while you are working in the terminal with git, you need to add the key to your ssh-agent. This should be valid until you reboot your machine.

ssh-add ~/.ssh/id_rsa

Now, when you pull, it should do so without prompting for your passphrase. I primarily do this when I have written convenience scripts to run between branches.