All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The Book of Allaah must be protected from anything that might suggest dispraising or degrading its status. So what is evident, Allaah knows best, is that any picture of a foot or shoe must be removed away from the Qur'an. Even if it is not a real foot, it is still a symbol for it. There is no need to keep this engraving, and it does not benefit a Muslim whatsoever. The love for the Prophet must be represented in following his Sunnah and guidance, and reading his biography. This would benefit a Muslim in this life and the hereafter. Anyway we draw your attention that there is no trace of the foot of the Prophet to support the claim that this is its engraving. The best that could be said about it is that it is an imaginary engraving based on the description of some people who saw him. Somebody described the Prophet to Al-Hassan Ibn Ali . He described his hands, legs, head and eyes, and his entire body and chest.
Allaah knows best.