diff --git a/src/protocol.h b/src/protocol.h
--- a/src/protocol.h
+++ b/src/protocol.h
@@ -61,7 +61,6 @@
 
     std::string GetCommand() const;
     bool IsCommandValid() const;
-    bool IsValidWithoutConfig(const MessageMagic &magic) const;
     bool IsOversized(const Config &config) const;
 
     SERIALIZE_METHODS(CMessageHeader, obj) {
diff --git a/src/protocol.cpp b/src/protocol.cpp
--- a/src/protocol.cpp
+++ b/src/protocol.cpp
@@ -118,13 +118,13 @@
                            strnlen(pchCommand.data(), COMMAND_SIZE));
 }
 
-static bool CheckHeaderMagicAndCommand(const CMessageHeader &header) {
+bool CMessageHeader::IsCommandValid() const {
     // Check the command string for errors
-    for (const char *p1 = header.pchCommand.data();
-         p1 < header.pchCommand.data() + CMessageHeader::COMMAND_SIZE; p1++) {
+    for (const char *p1 = pchCommand.data();
+         p1 < pchCommand.data() + CMessageHeader::COMMAND_SIZE; p1++) {
         if (*p1 == 0) {
             // Must be all zeros after the first zero
-            for (; p1 < header.pchCommand.data() + CMessageHeader::COMMAND_SIZE;
+            for (; p1 < pchCommand.data() + CMessageHeader::COMMAND_SIZE;
                  p1++) {
                 if (*p1 != 0) {
                     return false;
@@ -138,31 +138,6 @@
     return true;
 }
 
-bool CMessageHeader::IsCommandValid() const {
-    // Check start string
-    if (!CheckHeaderMagicAndCommand(*this)) {
-        return false;
-    }
-
-    return true;
-}
-
-/**
- * This is a transition method in order to stay compatible with older code that
- * do not use the config. It assumes message will not get too large. This cannot
- * be used for any piece of code that will download blocks as blocks may be
- * bigger than the permitted size. Idealy, code that uses this function should
- * be migrated toward using the config.
- */
-bool CMessageHeader::IsValidWithoutConfig(const MessageMagic &magic) const {
-    // Check start string
-    if (!CheckHeaderMagicAndCommand(*this)) {
-        return false;
-    }
-
-    return true;
-}
-
 bool CMessageHeader::IsOversized(const Config &config) const {
     // If the message doesn't not contain a block content, check against
     // MAX_PROTOCOL_MESSAGE_LENGTH.
diff --git a/src/seeder/bitcoin.cpp b/src/seeder/bitcoin.cpp
--- a/src/seeder/bitcoin.cpp
+++ b/src/seeder/bitcoin.cpp
@@ -135,7 +135,7 @@
                                       vRecv.begin() + nHeaderSize);
         CMessageHeader hdr;
         vRecv >> hdr;
-        if (!hdr.IsValidWithoutConfig(netMagic)) {
+        if (!hdr.IsCommandValid()) {
             // tfm::format(std::cout, "%s: BAD (invalid header)\n",
             // ToString(you));
             ban = 100000;
diff --git a/src/seeder/test/p2p_messaging_tests.cpp b/src/seeder/test/p2p_messaging_tests.cpp
--- a/src/seeder/test/p2p_messaging_tests.cpp
+++ b/src/seeder/test/p2p_messaging_tests.cpp
@@ -98,16 +98,15 @@
                                  PeerMessagingState::AwaitingMessages);
 
     // Seeder should respond with an ADDR message
-    const CMessageHeader::MessageMagic netMagic = Params().NetMagic();
     CMessageHeader header;
     CDataStream sendBuffer = testNode->getSendBuffer();
     sendBuffer >> header;
-    BOOST_CHECK(header.IsValidWithoutConfig(netMagic));
+    BOOST_CHECK(header.IsCommandValid());
     BOOST_CHECK_EQUAL(header.GetCommand(), NetMsgType::GETADDR);
 
     // Next message should be GETHEADERS
     sendBuffer >> header;
-    BOOST_CHECK(header.IsValidWithoutConfig(netMagic));
+    BOOST_CHECK(header.IsCommandValid());
     BOOST_CHECK_EQUAL(header.GetCommand(), NetMsgType::GETHEADERS);
 
     CBlockLocator locator;