diff --git a/Library/Homebrew/brew.rb b/Library/Homebrew/brew.rb
index cab8b2a852..ca712613e4 100644
--- a/Library/Homebrew/brew.rb
+++ b/Library/Homebrew/brew.rb
@@ -131,8 +131,6 @@ begin
     end
     exec "brew-#{cmd}", *ARGV
   else
-    raise "command made by bash not ruby: #{cmd}" if Commands.only_bash_command_list.include?(cmd)
-
     possible_tap = OFFICIAL_CMD_TAPS.find { |_, cmds| cmds.include?(cmd) }
     possible_tap = Tap.fetch(possible_tap.first) if possible_tap
 
diff --git a/Library/Homebrew/commands.rb b/Library/Homebrew/commands.rb
index d725a0bafd..0fd56c5838 100644
--- a/Library/Homebrew/commands.rb
+++ b/Library/Homebrew/commands.rb
@@ -197,8 +197,4 @@ module Commands
     file = HOMEBREW_CACHE/"all_commands_list.txt"
     file.atomic_write("#{commands(aliases: true).sort.join("\n")}\n")
   end
-
-  def only_bash_command_list
-    internal_commands.reject { |cmd| valid_internal_cmd?(cmd) }
-  end
 end
diff --git a/Library/Homebrew/dev-cmd/prof.rb b/Library/Homebrew/dev-cmd/prof.rb
index add6a5ae01..1fd6a762da 100644
--- a/Library/Homebrew/dev-cmd/prof.rb
+++ b/Library/Homebrew/dev-cmd/prof.rb
@@ -26,6 +26,8 @@ module Homebrew
 
     brew_rb = (HOMEBREW_LIBRARY_PATH/"brew.rb").resolved_path
     FileUtils.mkdir_p "prof"
+    cmd = args.named.first
+    raise UsageError, "#{cmd} is a Bash command!" if Commands.path(cmd).extname == ".sh"
 
     if args.stackprof?
       Homebrew.install_gem_setup_path! "stackprof"