Isaiah writes about the kingdom time (1000 years) promised to the nation Israel when their Messiah (the Lord Jesus) will rule over them (and the whole world). During this time peace will reign that man and animals will dwell together without fear. An example is in:
Isaiah 11:8 And the sucking child shall play on the hole of the asp, and the weaned child shall put his hand on the cockatrice’ den.
Read all of Isaiah 11.