Besieging Love of God

Heard in church today the bewitching song based on Psalm 139 and felt myself struck dumb by the line:

and with love everlasting you besiege me

I sat and couldn't get the image of the besieging love of God out of my head. As great powerful armies besieged cities in ancient times, so the love of God in Christ, lays siege to our hearts, encompassing them round and about.