כִּ֤י תִקְנֶה֙ עֶ֣בֶד עִבְרִ֔י שֵׁ֥שׁ שָׁנִ֖ים יַעֲבֹ֑ד וּבַ֨שְּׁבִעִ֔ת יֵצֵ֥א לַֽחָפְשִׁ֖י חִנָּֽם׃
Se comprares um servo Hebreu, seis anos ele servirá; e no sétimo sairá livre, de graça. {ס}
Mishnah Kiddushin
A Hebrew slave is acquired by money and by document; And acquires himself by years, by Jubilee, and by deduction from the purchase price. A Hebrew maidservant is greater in that she acquires herself by ‘signs [of physical maturity]’. He whose ear is bored is acquired by boring, and acquires himself by Jubilee or his master's death.
Mishnah Ketubot
And in the following cases there is no fine:If a man had intercourse with a female convert, a female captive or a slave-woman, who was redeemed, converted or freed after the age of three years and a day. Rabbi Judah says: a female captive who was redeemed is considered to be in her state of holiness (a virgin) even if she is of majority age. A man who had intercourse with his daughter, his daughter's daughter, his son's daughter, his wife's daughter, her son's daughter or her daughter's daughter does not pay the fine, because he forfeits his life, for his death is in the hands of the court, and he who forfeits his life pays no monetary fine for it is said, “And yet no other damage ensues he shall be fined” (Exodus 21:2.