It is narrated from Sayyiduna Ibn Amr (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: "A person does not have the right to divorce a woman whom he does not own (by marriage or purchase). A person also does not have the authority to free someone who is not his slave, nor does he have the right to make a vow regarding something he does not own. And there is no vow in disobedience to Allah."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 6932