'Seventh Year' in the Bible

Beware that there be not a thought in thy wicked heart, saying, The seventh year, the year of release, is at hand; and thy eye shall be evil against thy poor brother, and thou shalt give him naught; and he shall cry to the LORD against thee, and it shall be sin to thee.

And if thy brother, a Hebrew man, or a Hebrew woman, shall be sold to thee, and serve thee six years; then in the seventh year thou shalt let him go free from thee.