If a slave marries without his master’s permission, he is a fornicator

The Hadīth means that if a slave marries without the permission of his master, his marriage is invalid and the contract is consequently null and void. The slave would therefore be considered as a fornicator. So, the marriage must be nullified and the slave must be separated from the woman he married without his master’s permission, because slaves are not entitled to get married without their masters’ approval.