A charge to keep I have

Charles Wesley, 1762, writing on Leviticus 8:35 (via Matthew Henry). Almost universally set to Boylston, at least in the USA. The Cyber Hymnal (TCH) suggests Kentucky and Galway as alternatives. I'd be inclined to go with almost anything rather than the ubiquitous Boylston.

The text

A charge to keep I have,
A God to glorify,
A never-dying soul to save,
And fit it for the sky.

To serve the present age,
My calling to fulfill:
O may it all my powers engage
To do my Master’s will!

Arm me with jealous care,
As in Thy sight to live;
And O Thy servant, Lord, prepare
A strict account to give!

Help me to watch and pray,
And on Thyself rely,
Assured, if I my trust betray,
I shall forever die.

Word's Hymnal for Worship & Celebration (#448) and Celebration Hymnal (where it is the ominous #666!) soften the fourth stanza, removing the mention of eternal death:

Help me to watch and pray,
And still on Thee rely,
O let me not my trust betray,
But press to realms on high.

I would stick with Wesley's wording here, although I am not a fan of the annihilationism he seems to be espousing.