St. John Chrysostom: “If you knew how quickly people would forget you after your death, you would not seek in your life to please anyone but God”... or Allah?

This quote from John Chrysostom has been making the cyber-rounds. I suspect most people rightly resonate with the profound depth of the words. My first reaction though was.... great quote... where exactly did John Chrysostom write this? What source does this quote come from?

Documentation
A cursory search produced a seemingly complete absence of documentation of the quote in this particular English form. The quote in this form seems recent to the last few years. 

 A curious version also circulating states, "If you knew how fast people would forget you after death, you would not live your life to please anyone but Allah." This English version seems to predate the Chrysostom English version, but not by all that many years. It also appears to be cited much more by those devoted to Islam.

Conclusion
Without finding any meaningful documentation, the quote may be someone's commentary of what either John Chrysostom wrote or what Islam teaches. It is within the realm of possibility that both quotes developed independently of each other, but that the English versions are so similar points towards a common source.  Someone borrowed from someone! 

For my friends familiar with the extant writings of John Chrysostom, I would be interested in any leads as to anything sounding vaguely familiar in his writings (for instance, note some of the similarities in this quote). For those of you knowledgeable of Islam: where do you think the quote comes from?  Do you think a Christian plagiarized an Islamic source?