The pager can be configured globally, for one run of a command, or as I'll explain in this post, for a specific command.
I explore all of this in Optimize the way Git displays the output of commands.
Let's assume a git configuration that uses less for any command that need a
pager. Perhaps you'd like for the git show to work a bit differently than
other commands. You want it to use less with the -F and -X flags.
A custom pager command can be set for any command in the [pager] section of
the ~/.gitconfig file.
[pager]
show = "less -FX"
If you want to turn off the pager for a specific command, set it to the boolean
value false instead.
[pager]
show = false
See man git-config for more details in the core.pager and pager.<cmd>
sections.