Is not this the kind of fasting I have chosen:
to loose the chains of injustice
and untie the cords of the yoke,
to set the oppressed free
and break every yoke?

Is it not to share your food with the hungry
and to provide the poor wanderer with shelter—
when you see the naked, to clothe them,
and not to turn away from your own flesh and blood?

Then your light will break forth like the dawn,
and your healing will quickly appear;
then your righteousness will go before you,
and the glory of the Lord will be your rear guard.

Then you will call, and the Lord will answer;
you will cry for help, and he will say: Here am I.
“If you do away with the yoke of oppression,
with the pointing finger and malicious talk,

and if you spend yourselves in behalf of the hungry
and satisfy the needs of the oppressed,
then your light will rise in the darkness,
and your night will become like the noonday.

Isaiah 58:6-10