Can someone paraphrase this quote for me please? "On an alter of prejudice we crucify our own, yet the blood of all children is the color of...

What Don Williams is saying in this quote is basically
that all people are fundamentally the same.  He is saying that because of this racism is
a pointless and harmful thing.

In the first part of the
quote, he is saying that we, essentially, sacrifice our own good to prejudice.  In other
words, we hurt ourselves when we give in to prejudice and
racism.

In the second part of the quote, he says that we
hurt ourselves because we are all equal before God.  He says that we are all God's
children and so when we hurt other people, we're truly hurting
ourselves.

So this quote is saying that we are all made in
the image of God and we are all part of God's creation and so when we hurt each other
through racism we are hurting ourselves.