From 1 Kings 17, the story of fleeing Elijah and the widow to whom he is directed by God to meet in the Phoenician town of Zarephath it a tough one at first glance. The widow is down to her last meal for herself and her son. Elijah requests that she bring him some bread. She protests, explaining how she only has enough for this last meal. Elijah promises that his God - Yahweh - will not let her resources run out. She knows her gods won't be helping her. Should she trust this strange nutter who just landed in town?
Continuing Mark 12, Jesus is in the Jerusalem Temple with his dimwit disciples. They are taken in by the magnificence of the Temple, the lofty, prestigious status of the priests and scribes, and the big donations cascading into the Temple's collection box from rich people. Their attention is focused on all of the wrong things!
Then a pathetic widow steps up to the collection box and plunks down two tinny, almost worthless coins. Now Jesus has a life example to make his point. Jesus then teaches his disciples about how to measure true faithfulness instead of being enrapt by outward displays of false piety.
See how each widow provides a poignant frame of reference for genuine faithfulness in the sermon video below.