There is a fountain fill'd with blood,
Drawn from Emmanuel's veins;
And sinners, plunged beneath that flood,
Lose all their guilty stains.

The dying thief rejoiced to see
That fountain in his day;
And there have I, as vile as he,
Wash'd all my sins away.

Dear dying Lamb, Thy precious blood
Shall never lose its power,
Till all the ransom'd church of God
Be saved, to sin no more.

E'er since, by faith, I saw the stream
Thy flowing wounds supply,
Redeeming love has been my theme,
And shall be till I die.

Then in a nobler, sweeter song,
I'll sing Thy power to save;
When this poor lisping stammering tongue
Lies silent in the grave.

Lord, I believe Thou hast prepared
(Unworthy though I be)
For me a blood-bought free reward,
A golden harp for me!

'Tis strung and tuned for endless years,
And form'd by power divine,
To sound in God the Father's ears
No other name but Thine.

William Cowper

http://www.poemhunter.com/poem/olney-hymn-15-praise-for-the-fountain-opened/