Love Constraining to Obedience

This is a great hymn from William Cowper that Timothy Keller mentioned in one of his messages. I wish I could learn it on guitar but so far can't quite get it.

Chorus:
To see the Law by Christ fulfilled,
To hear His pardoning voice,
Changes a slave into a child
And duty into choice.

1. No strength of nature can suffice
To serve the Lord aright
And what she has, she misapplies,
For want of clearer light.

2. How long beneath the Law I lay
In bondage and distress
I toiled the precept to obey,
But toiled without success.

3. Then to abstain from outward sin
Was more than I could do
Now if I feel its power within
I feel I hate it too.

4. Then all my servile works were done,
A righteousness to raise
Now, freely chosen in the Son,
I freely choose His ways.