This window is a depiction of the parable of the Sower in the Gospel of Mark, chapter four.
Jesus told a parable-story, saying,
"Listen. What do you make of this? A farmer planted seed. As he scattered the seed, some of it fell on the road and birds ate it. Some fell in the gravel; it sprouted quickly but didn't put down roots, so when the sun came up it withered just as quickly. Some fell in the weeds; as it came up, it was strangled among the weeds and nothing came of it. Some fell on good earth and came up with a flourish, producing a harvest exceeding his wildest dreams."
Then Jesus explained the story:
"The farmer plants the Word of God. Some people are like the seed that falls on the hardened soil of the road. No sooner do they hear the Word than Satan snatches away what has been planted in them.
"And some are like the seed that lands in the gravel. When they first hear the Word, they respond with great enthusiasm. But there is such shallow soil of character that when the emotions wear off and some difficulty arrives, there is nothing to show for it.
"The seed cast in the weeds represents the ones who hear the kingdom news but are overwhelmed with worries about all the things they have to do and all the things they want to get. The stress strangles what they heard, and nothing comes of it.
"But the seed planted in the good earth represents those who hear the Word [of God concerning Jesus Christ], embrace it, and produce a harvest beyond their wildest dreams."
-Mark 4:3-8, The Message
The Paxton Window was given in memory of William Miller Paxton (1824-1904), who served as the fourth minister of First Presbyterian Church of Pittsburgh from 1851 to 1865.