diff --git a/gravity.sh b/gravity.sh
index af0e2278..280ce6c1 100755
--- a/gravity.sh
+++ b/gravity.sh
@@ -330,7 +330,7 @@ gravity_ParseFileIntoDomains() {
       }' "${source}" > "${destination}.exceptionsFile.tmp"
 
       # Remove exceptions
-      grep -F -x -v -f "${destination}.exceptionsFile.tmp" "${destination}" > "${source}"
+      comm -23 "${destination}" <(sort "${destination}.exceptionsFile.tmp") > "${source}"
       mv "${source}" "${destination}"
     fi
 
@@ -449,7 +449,7 @@ gravity_Whitelist() {
   echo -ne "  ${INFO} ${str}..."
 
   # Print everything from preEventHorizon into whitelistMatter EXCEPT domains in $whitelistFile
-  grep -F -x -v -f "${whitelistFile}" "${piholeDir}/${preEventHorizon}" > "${piholeDir}/${whitelistMatter}"
+  comm -23 "${piholeDir}/${preEventHorizon}" <(sort "${whitelistFile}") > "${piholeDir}/${whitelistMatter}"
 
   echo -e "${OVER}  ${INFO} ${str}"
 }