I believe this is what you're looking for:

Under the blood of Jesus,
Safe in the Shepherd's fold.
Under the blood of Jesus,
Safe while the ages roll.
Safe though the worlds may crumble,
Safe though the stars grow dim.
Under the blood of Jesus,
I am secure in Him.

You can find sheet music here:
http://www.rvgrace.com/hymns/Under_the_Blood_of_Jesus.htm

God bless!
Steve

our church played this hymn recently and it's been on my mind all week. It's a very old song but the words are the truth's of life