diff --git a/extensions/hibernate-orm/runtime/src/main/java/io/quarkus/hibernate/orm/runtime/session/TransactionScopedSession.java b/extensions/hibernate-orm/runtime/src/main/java/io/quarkus/hibernate/orm/runtime/session/TransactionScopedSession.java
index 21c89cf29d9fec..f4046bfaee1233 100644
--- a/extensions/hibernate-orm/runtime/src/main/java/io/quarkus/hibernate/orm/runtime/session/TransactionScopedSession.java
+++ b/extensions/hibernate-orm/runtime/src/main/java/io/quarkus/hibernate/orm/runtime/session/TransactionScopedSession.java
@@ -83,7 +83,7 @@ SessionResult acquireSession() {
                 return new SessionResult(session, false, true);
             }
             Session newSession = sessionFactory.openSession();
-            newSession.joinTransaction();
+            // The session has automatically joined the JTA transaction when it was constructed.
             transactionSynchronizationRegistry.putResource(sessionKey, newSession);
             // No need to flush or close the session upon transaction completion:
             // Hibernate ORM itself registers a transaction that does just that.