Lamentations 3:39: Why should a sinful man complain

Why should a sinful man complain,
Indulged with a reprieve.
Guilty of death and endless pain,
Yet suffer'd still to live!
I dare not murmur at the rod,
Whate'er on earth I feel.
But praise the mercies of my God,
Which keep me out of hell.

Conscious of what my sins demand,
I bow to my distress.
Adore a Father's gentle hand,
Whose chastisements are grace:
And if I answer the intent
Of His afflicting love,
I'll praise Him for my punishment
In endless songs above.