What are the lessons from the story of the Samaritan and the Calf?

The Qur’an mentions the calf that the Samiri made from gold. The wisdom behind mentioning this might be to illustrate some proofs of the prophethood of Muhammad, peace and blessings be upon him, as his narration of unseen events he did not witness indicates that he received divine revelation.

Another wisdom might be to show the ignorance of the Jews and idolaters. The Jews worshipped a calf they made themselves, which indicates their foolishness and points to their complete ignorance, as mentioned in the tafsir of Al-Uthaymeen.