Here is a page on Peter Marshall, with many of his quotes including this prayer read as part of Youth Sunday at BG First Presbyterian Church in 1973:

“We know that Thou hast not promised to surround us with immunity from all the ills to which flesh is heir. We only pray that when they come, if come they must, they shall find us unafraid and with adequate resources to meet them. Give us a constant faith and a steady courage, that we may neither whimper nor in peevish petulance complain before Thee. ” (“To Face the Future Without Fear”)