The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
The whole essay is much worth reading, and only 8 pages (at pp. 7-14 here). Note that it's the version left in Jackson's papers when he died in 1954, and it hasn't been edited for style or substance.
UPDATE: At the (implicit) suggestion of commenter mad_kalak, I'm posting a bit more of the context for the quote; Justice Jackson is writing about his family's beliefs about religion:
The "fear of God" was no more in my people [his family] than fear of anything else. They faced the vicissitudes of life without leaning on religion, its hardship without mitigation by what the Communists call "the opiate" of religion…. When death approached there was no call for help, no conversion, no repentance, no last rites. They had lived their lives, poor things perhaps but their own, and what they had done would have to stand.
Death they simply took as in the natural order of things…. Who ordained it, what it meant in terms of the personality, and what if anything lies beyond it they knew not. But to it they would go alone, yet with all mankind for company, and they expected to get through it as well as most. I was never impressed that they expected Heavenly reward and I am sure they had no shudders about Hell fire though both ideas were rife in the community.