"For this reason the Father loves me, because I lay down my life that I may take it up again. No one takes it from me, but I lay it down of my own accord. I have authority to lay it down, and I have authority to take it up again. This charge I have received from my Father."
John 10:17-18 ESV
A powerful statement by Christ. He lays down his life of His own accord. He is not forced or obligated to lay His life down.
Jesus Christ did not have to die for guilty sinners. If he didn't, this would not change His character of love (after all, we deserve God's wrath due to our sin nature). Yet, Christ chose simply, from His sheer will, to die for us in our stead.
The more you have to sacrifice without getting something in return, the greater you can show someone love.
For example, it is no big deal to lend someone one hundred dollars if I will get it back in return (especially if there is interest). But to be a donor to someone in a surgery that will cost you your life where you know that person will not even say 'thank you' is a much greater task.
In an even greater way, Christ showed His great love by dying on the cross and taking the wrath of God in our stead.
What a gracious and loving God we serve! Let us follow in His footsteps as His ambassadors.