diff --git a/modules/spamfilter/spamfilter.controller.php b/modules/spamfilter/spamfilter.controller.php
index 435aa3802..0e75d92ee 100644
--- a/modules/spamfilter/spamfilter.controller.php
+++ b/modules/spamfilter/spamfilter.controller.php
@@ -50,9 +50,8 @@ class SpamfilterController extends Spamfilter
 			if($grant->manager) return;
 		}
 
-		$oFilterModel = getModel('spamfilter');
 		// Check if the IP is prohibited
-		$output = $oFilterModel->isDeniedIP();
+		$output = SpamfilterModel::isDeniedIP();
 		if(!$output->toBool()) return $output;
 		// Check if there is a ban on the word
 		$filter_targets = [$obj->title, $obj->content, $obj->tags ?? ''];
@@ -71,7 +70,7 @@ class SpamfilterController extends Spamfilter
 				}
 			}
 		}
-		$output = $oFilterModel->isDeniedWord(implode("\n", $filter_targets));
+		$output = SpamfilterModel::isDeniedWord(implode("\n", $filter_targets));
 		if(!$output->toBool())
 		{
 			return $output;
@@ -79,7 +78,7 @@ class SpamfilterController extends Spamfilter
 		// Check the specified time beside the modificaiton time
 		if($obj->document_srl == 0)
 		{
-			$output = $oFilterModel->checkLimited();
+			$output = SpamfilterModel::checkLimited();
 			if(!$output->toBool()) return $output;
 		}
 		// Save a log
@@ -103,9 +102,8 @@ class SpamfilterController extends Spamfilter
 			if($grant->manager) return;
 		}
 
-		$oFilterModel = getModel('spamfilter');
 		// Check if the IP is prohibited
-		$output = $oFilterModel->isDeniedIP();
+		$output = SpamfilterModel::isDeniedIP();
 		if(!$output->toBool()) return $output;
 		// Check if there is a ban on the word
 		if($is_logged)
@@ -116,12 +114,12 @@ class SpamfilterController extends Spamfilter
 		{
 			$text = $obj->content . ' ' . $obj->nick_name . ' ' . $obj->homepage;
 		}
-		$output = $oFilterModel->isDeniedWord($text);
+		$output = SpamfilterModel::isDeniedWord($text);
 		if(!$output->toBool()) return $output;
 		// If the specified time check is not modified
 		if(!$obj->__isupdate)
 		{
-			$output = $oFilterModel->checkLimited();
+			$output = SpamfilterModel::checkLimited();
 			if(!$output->toBool()) return $output;
 		}
 		unset($obj->__isupdate);
@@ -197,7 +195,7 @@ class SpamfilterController extends Spamfilter
 			return;
 		}
 
-		$output = SpamfilterModel::getInstance()->isDeniedIP();
+		$output = SpamfilterModel::isDeniedIP();
 		if (!$output->toBool())
 		{
 			return $output;
@@ -219,7 +217,7 @@ class SpamfilterController extends Spamfilter
 			return;
 		}
 
-		$output = SpamfilterModel::getInstance()->isDeniedIP();
+		$output = SpamfilterModel::isDeniedIP();
 		if (!$output->toBool())
 		{
 			return $output;
@@ -240,16 +238,15 @@ class SpamfilterController extends Spamfilter
 		$logged_info = Context::get('logged_info');
 		if($logged_info->is_admin == 'Y') return;
 
-		$oFilterModel = getModel('spamfilter');
 		// Check if the IP is prohibited
-		$output = $oFilterModel->isDeniedIP();
+		$output = SpamfilterModel::isDeniedIP();
 		if(!$output->toBool()) return $output;
 		// Check if there is a ban on the word
 		$text = $obj->title . ' ' . $obj->content;
-		$output = $oFilterModel->isDeniedWord($text);
+		$output = SpamfilterModel::isDeniedWord($text);
 		if(!$output->toBool()) return $output;
 		// Check the specified time
-		$output = $oFilterModel->checkLimited(TRUE);
+		$output = SpamfilterModel::checkLimited(TRUE);
 		if(!$output->toBool()) return $output;
 		// Save a log
 		$this->insertLog();
diff --git a/modules/spamfilter/spamfilter.model.php b/modules/spamfilter/spamfilter.model.php
index feee6bf42..dcd23d6cb 100644
--- a/modules/spamfilter/spamfilter.model.php
+++ b/modules/spamfilter/spamfilter.model.php
@@ -7,17 +7,10 @@
  */
 class SpamfilterModel extends Spamfilter
 {
-	/**
-	 * @brief Initialization
-	 */
-	function init()
-	{
-	}
-
 	/**
 	 * @brief Return the user setting values of the Spam filter module
 	 */
-	function getConfig()
+	public static function getConfig()
 	{
 		return ModuleModel::getModuleConfig('spamfilter') ?: new stdClass;
 	}
@@ -25,7 +18,7 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Return the list of registered IP addresses which were banned
 	 */
-	function getDeniedIPList($sort_index = 'regdate')
+	public static function getDeniedIPList($sort_index = 'regdate')
 	{
 		$args = new stdClass();
 		$args->sort_index = $sort_index;
@@ -38,12 +31,12 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Check if the ipaddress is in the list of banned IP addresses
 	 */
-	function isDeniedIP()
+	public static function isDeniedIP()
 	{
 		$ip_list = Rhymix\Framework\Cache::get('spamfilter:denied_ip_list');
 		if ($ip_list === null)
 		{
-			$ip_list = $this->getDeniedIPList();
+			$ip_list = self::getDeniedIPList();
 			Rhymix\Framework\Cache::set('spamfilter:denied_ip_list', $ip_list);
 		}
 		if (!count($ip_list))
@@ -75,7 +68,7 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Return the list of registered Words which were banned
 	 */
-	function getDeniedWordList($sort_index = 'hit')
+	public static function getDeniedWordList($sort_index = 'hit')
 	{
 		$args = new stdClass();
 		$args->sort_index = $sort_index;
@@ -86,12 +79,12 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Check if the text, received as a parameter, is banned or not
 	 */
-	function isDeniedWord($text)
+	public static function isDeniedWord($text)
 	{
 		$word_list = Rhymix\Framework\Cache::get('spamfilter:denied_word_list');
 		if ($word_list === null)
 		{
-			$word_list = $this->getDeniedWordList();
+			$word_list = self::getDeniedWordList();
 			Rhymix\Framework\Cache::set('spamfilter:denied_word_list', $word_list);
 		}
 		if (!count($word_list))
@@ -128,7 +121,7 @@ class SpamfilterModel extends Spamfilter
 				$args->word = $word;
 				executeQuery('spamfilter.updateDeniedWordHit', $args);
 
-				$config = $this->getConfig();
+				$config = self::getConfig();
 
 				if($config->custom_message)
 				{
@@ -161,9 +154,9 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Check the specified time
 	 */
-	function checkLimited($isMessage = FALSE)
+	public static function checkLimited($isMessage = FALSE)
 	{
-		$config = $this->getConfig();
+		$config = self::getConfig();
 
 		if($config->limits != 'Y') return new BaseObject();
 		$limit_count = $config->limits_count ?: 3;
@@ -177,7 +170,7 @@ class SpamfilterModel extends Spamfilter
 			}
 		}
 
-		$count = $this->getLogCount($interval);
+		$count = self::getLogCount($interval);
 
 		// Ban the IP address if the interval is exceeded
 		if($count>=$limit_count)
@@ -272,7 +265,7 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Check if the trackbacks have already been registered to a particular article
 	 */
-	function isInsertedTrackback($document_srl)
+	public static function isInsertedTrackback($document_srl)
 	{
 		$oTrackbackModel = getModel('trackback');
 		if (is_object($oTrackbackModel) && method_exists($oTrackbackModel, 'getTrackbackCountByIPAddress'))
@@ -289,7 +282,7 @@ class SpamfilterModel extends Spamfilter
 	/**
 	 * @brief Return the number of logs recorded within the interval for the specified IPaddress
 	 */
-	function getLogCount($time = 60, $ipaddress='')
+	public static function getLogCount($time = 60, $ipaddress='')
 	{
 		if(!$ipaddress) $ipaddress = \RX_CLIENT_IP;