The Catechism in Questions & Answers

155. Which parable calls for us to love our neighbour?

The greatest of the commandments are to love God and our neighbour. With the story of the Good Samaritan, Jesus illustrated who this neighbour is, and that loving our neighbour means that we must not close our eyes to the distress of others, but rather provide help.

The double commandment of love: see Questions 282. et seq.

“Then Jesus answered and said: ‘A certain man went down from Jerusalem to Jericho, and fell among thieves, who stripped him of his clothing, wounded him, and departed, leaving him half dead. Now by chance a certain priest came down that road. And when he saw him, he passed by on the other side. Likewise a Levite, when he arrived at the place, came and looked, and passed by on the other side. But a certain Samaritan, as he journeyed, came where he was. And when he saw him, he had compassion. So he went to him and bandaged his wounds, pouring on oil and wine; and he set him on his own animal, brought him to an inn, and took care of him. On the next day, when he departed, he took out two denarii, gave them to the innkeeper, and said to him, “Take care of him; and whatever more you spend, when I come again, I will repay you”’.”
Luke 10: 30-35