...on the palm of my hands....

I have engraved you on the palms of my hands.  Isaiah 49:16
The Lord assured us of His faithfulness, that He cannot forget us because He has written us on His hand.
As my teenage daughter writes messages to herself of things she must not forget on her hand, and many times I have observed, all the way up her arm, so I always thought this was the illustration here.
God is being cute, writing us all on His hand so as not to forget us, like some kind of eternal tattoo.
But there's more:  The engraving of me on His hands happened on the Cross!

Engraved in blood
Forged by nails
The Name above all
Has carved my own.
Deep within His palm I lie
Within His wounds is where I hide.

Eternity still displays the scars because the work of the Cross is yet unfinished in as much as not every knee is bowed, not every tongue has confessed the Name of Jesus.
Call upon the Name of the Lord and be saved.