If you seek the Cross of Christ, take my heart; there you will find the suffering Lord.
SaintClare of Montefalco. After her death, the Church approved of an operation to examine her heart. A perfectly formed crucifix was found imprinted in the flesh of her heart, along with the crown of thorns, nails, spear, and other instruments of the Passion, naturally formed in the tissue.
That is very humbling to read about St Clare and her post mortem heart. How she must have suffered.