We sang this last night at our new church.  David and I were both struck by it and after the service read through it again individually.  That is one of the benefits of hymnbooks - you can spend some time meditating on the words as they don't disappear off a screen!  Neither of us had sung this hymn before, although we've been Christians for many years.  I had read one of the couplets before, and it was good to see it in context.

Exhortation to Prayer 

What various hindrances we meet
In coming to a mercy seat!
Yet who that knows the worth of prayer,
But wishes to be often there?

Prayer makes the darken'd cloud withdraw,
Prayer climbs the ladder Jacob saw,
Gives exercise to faith and love,
Brings every blessing from above.

Restraining prayer, we cease to fight;
Prayer makes the Christian's armour bright;
And Satan trembles when he sees
The weakest saint upon his knees.

While Moses stood with arms spread wide,
Success was found on Israel's side;
But when through weariness they fail'd,
That moment Amalek prevail'd.

Have you no words? Ah, think again,
Words flow apace when you complain,
And fill your fellow-creature's ear
With the sad tale of all your care.

Were half the breath thus vainly spent
To heaven in supplication sent,
Your cheerful song would oftener be,
"Hear what the Lord has done for me."