Isaiah 53:6

If you extend your soul to the hungry
And satisfy the afflicted soul,
Then your light shall dawn in the darkness,
And your darkness shall be as the noonday.

What does it mean to satisfy the afflicted soul here in the passage?

Earlier in the chapter the word ‘afflict’ is used twice: v3 and v5.  It is a subtle reference to the proper afflicting of the soul that was supposed to take place on the day of atonement, the day when Israel had the record of their sins cleansed from the temple.

However, the chapter has been describing so far details that outward signs of righteousness are not what God is interested in, but rather inward righteousness expressed in outward acts of caring for others.

Here in v10 Isaiah is creating a play on words by asking the people to satisfy to afflicted soul, to make sure that no one is afflicted any more, even though afflicting the soul is prescribed.  What he means by the afflicted soul is those that are lacking justice, or have not received proper treatment from those professing an outward show.  When we work from an unselfish principle to relieve affliction, we will then be properly afflicting our souls.