The wonder of it all!

Gen 4-6; Matt 2

'Then the LORD put a mark on Cain so that no one who found him would kill him.' (Gen 2:15)

When you believed in the Messiah, you were sealed with the promised Holy Spirit who is the guarantee of our inheritance until God redeems his own possession for his praise and glory. (Eph 1:13,14)

Having killed his brother Abel, Cain was 'punished' by God by being cast out of His presence. Nevertheless, God, in His grace, put a mark on Cain to protect him from physical death.
As blood-bought believers, we are delivered from the certainty of eternal spiritual death by the Lord Jesus ('For the wages of sin is death' Rom 6:23). The Lord tasted death on our behalf, that we might live. And He too puts a mark on us - a seal - that marks us out as His precious possession. We are sealed by the Holy Spirit, who is the guarantee of our inheritance until we see Jesus face to face! Hallejulah! What a wonder of wonders!

"See what love the Father has given us, that we should be called children of God; and so we are." (1 John 3)