"O you who have believed" means: those who have affirmed with their tongues. It was revealed regarding the hypocrites. "Let not your wealth and your children divert you from the remembrance of Allah," meaning: from the belief in Allah.
﴿يَا أَيهَا الَّذين آمنُوا﴾ يَعْنِي: أقرُّوا بِاللِّسَانِ نزلتْ فِي الْمُنَافِقين ﴿لَا تُلْهِكُمْ أَمْوَالُكُمْ وَلا أَوْلَادكُم عَن ذكر الله﴾ عَن الْإِيمَان بِاللَّه
