--- a/git.rst	Thu Jan 16 13:32:54 2020 +0200
+++ b/git.rst	Thu Jan 16 13:42:03 2020 +0200
@@ -534,6 +534,11 @@
   $ git grep $PATT
   $ git grep -i $PATT -- '*.[ch]'
 
+To search for string in commit messages::
+
+  $ git log --grep $PATT
+  $ git log --grep $PATT --all
+
 To search in all history::
 
   $ git log -S$PATT