You don’t even need a physical mark, we can use the pattern of veins you have like a barcode. No need for chips or tattoos.

To add: pushing the vaccine passport as the mark can be dangerous too (fight against it of course, I will with every ounce of my being), but if it is defeated are we to show God as a liar? What would the unbelieving think? It would be used against us.

You don’t even need a physical mark, we can use the pattern of veins you have like a barcode. No need for chips or tattoos.