A good place to start is the Book of John in the New Testament. John 17:23 shows Jesus praying in the garden of Gethsemane just hours before He is to go to His Father, GOD. (Jesus is going to be crucified.) He asked the Father to make known to us that GOD loves us just as much as He (GOD) loves Him (Jesus).
John 17:23 Amplified Version
I in them and You in Me, in order that they may become
one and perfectly united, that the world may know and
[definitely] recognize that You sent Me and that You have
loved them [even] as You have loved Me.