Within this verse is a perfectly simple but totally effective description of the Trinity.  The Trinity being three persons in one Godhead… Father, Son, and Holy Spirit.  First, we are called or summoned to salvation through the the Gospel Message by the Holy Spirit as we are wooed or drawn in.  For the Holy Spirit shows us very plainly our shortcomings and convicts us… so that we may be saved.  Next, we need to grasp just how greatly valued, esteemed, and loved we are by God the Father. For who else would give His only Son to die on a cross for all that we might have eternal life? (John 3:16)  Finally, know you belong to Jesus who watches over you to keep you safe. (John 17:12)   So just think of it…we are His and He is ours, and no one can ever snatch us out of His hand. (John 10:28)