This verse speaks of the pledge which Allah had made the Israelites take, and the few people it refers to as having been true to the pledge were those who acted upon the Shari'ah of Sayyidna Musa (علیہ السلام) (Moses) as long as it was in force, and when it was abrogated, followed the Shari` ah of Sayyidna Muhammad ﷺ .
Injunctions and related considerations
(1) This verse brings out the basic elements common to Islam and all the earlier Shari` ah: Tauhid توحید (the doctrine of Unity or Oneness); service to one's parents, relations, orphans and the needy; being gentle in speaking to all human beings; Salah نماز and Zakah زکاۃ .
(2) The verse asks us to adopt a gentle tone and an open-hearted manner in speaking to others, whether they are good or evil, pious or impious, orthodox or aberrant, followers of Sunnah or adherents to partitive innovations in it. In religious matter, however, one should not try to hide the truth for the sake of pleasing people or of winning their approval. The Holy Qur'an tells us that when Allah sent Sayyidna Musa and Sayyidna Harun (Moses and Aaron) (علیہم السلام) to the Pharaoh فرعون ، He instructed them to use gentle and soft words (20:42). None of us who addresses another today can be superior to Sayyidna Musa (علیہ السلام) ، nor can the man addressed be viler than the Pharaoh فرعون .
Talha ibn ` Umar recounts that once he said to the great master of the Sciences of Exegesis and Hadith, 'At-a' عطاء ، "One can see around you people who are not quite orthodox in their beliefs. As for me, I am rather short-tempered. If such people come to me, I deal with them harshly." ` Ata' replied, "Do not behave like this," and, reciting the present verse, he added, Allah has commanded us to speak to people politely. When Jews and Christians all are to be treated like this, would this commandment not apply to a Muslim, no matter what kind of a man he is?" (Qurtubi)