How do we know the doctrine of selfishness is true?

The parable of the rich man serves as a poignant warning against selfishness. The rich man is not condemned for specific overt sins but rather for his indifference to the needs of Lazarus, who lay at his gate. This suggests that neglecting the welfare of others is a grave matter. Scripture emphasizes that true faith manifests itself in love and concern for others, contrasting sharply with the self-serving tendencies of the rich man. In the eyes of God, a life lived in selfish pursuit is destined for ruin, as seen in Matthew 25, where failing to assist those in need results in judgment.