As described in Durable Subscribers for Topics, messages published to topics are only consumed by active subscribers to the topic; otherwise the messages are not consumed and cannot be retrieved later. You can create a durable subscriber that ensures messages published to a topic are received by the subscriber, even if it is not currently running. For queues, messages remain on the queue until they are either consumed by a Message Consumer, the message expiration time has been reached, or the maximum size of the queue is reached.