The servant is the man who does not put his life at stake, the man who wants to conserve his life, wants to be conserved (servus). By raising oneself above life, by looking at death directly, one acceeds to lordship: to the for-itself [pour soi, fur sich], to freedom, to recognition. Freedom must go through the putting at stake of life (Daransetzen des Lebens). The lord is the man who has had the strength to endure the anguish of death and to maintain the work of death.

Derrida, "From Restricted to General Economy," 254

It is as if, then, the stranger could save the master and liberate the power of his host; it's as if the master, qua master, were prisoner of his place and his power, of his ipseity, of his subjectivity (his subjectivity is hostage). So it is indeed the master, the one who invites, the inviting host, who becomes the hostage - and who really always has been. And the guest, the invited hostage, becomes the one who invites the one who invites, the master of the host. The guest becomes the host's host. The guest (hôte) becomes the host (hôte) of the host (hôte).
…the master of the house is at home, but nonetheless he comes to enter his home through the guest - who comes from outside. The master thus enters from the inside as if he came from the outside.

Derrida, Of Hospitality, 123-25