Originally from
李贺's (mid-Tang)
《金铜仙人辞汉歌》:
衰兰送客咸阳道,天若有情天亦老 - 'Withering orchids see off the traveler on the Xianyang road; if heaven had feelings, heaven too would grow old.' Later given new life by
毛泽东 in
《七律·人民解放军占领南京》:
天若有情天亦老,人间正道是沧桑 - Mao's couplet is what most modern readers know.