The Adequacy of God

So I've been reading J.I. Packer's Knowing God and one of the last chapters is titled The Adequacy of God. He has spent the majority of this chapter touting Paul's letter to the Romans and how it reveals a lot about the mystery of the Gospel. At any rate, Packer's is writing about the end of Romans 8, "If God is for us, who can be against us..." and pulls out this piece of poetry from Toplady (an 18th century Christian):

A sovereign protector I have, 
    Unseen, yet for ever at hand; 
Unchangeably faithful to save, 
    Almighty to rule and command. 
He smiles, and my comforts abound; 
    His grace as the dew shall descend, 
And walls of salvation surround 
    The soul He delights to defend.