"As for the orphan, do not oppress him," meaning: do not oppress him by denying him the right which Allah has commanded [to be given to him].
﴿فَأَما الْيَتِيم فَلَا تقهر﴾ لَا تَقْهَرْهُ فَتَمْنَعْهُ حَقَّهُ الَّذِي أَمر الله بِهِ