"In that day this song shall be sung"

Isaiah 26 

In that day shall this song be sung in the land of Judah; We have a strong city; salvation will God appoint for walls and bulwarks.

2 Open ye the gates, that the righteous nation which keepeth the truth may enter in.

3 Thou wilt keep him in perfect peace, whose mind is stayed on thee: because he trusteth in thee.

4 Trust ye in the Lord for ever: for in the Lord Jehovah is everlasting strength: