At the cross we see ourselves at our worst and God at his best.
We are powerless, sinners, ungodly, and God's enemies. God demonstrates his great love toward us by giving his Son, and by the Son assuming responsibility for our sins, and bearing their punishment. If Christ were not God then the cross would not be the demonstration of his love but a great act of compassion by a third party. The reality is that the cross is the self-giving of God; of the Father not sparing his own Son, of the Son giving himself for our sins, laying down his life for his sheep. We measure his love for us not by looking at our present experience, not by looking inwardly, not by looking at our circumstances, but by taking our eyes off of ourselves and gazing upon Christ crucified. As I said, at the cross we see ourselves at our worst and God at his best.
Here are words to meditate upon again and again from George Smeaton (1814-1889):
Jesus was visited with penal suffering because he appeared before God only in the guise of our accumulated sin; not therefore as a private individual, but as a representative; sinless in himself, but sin covered; loved as a Son, but condemned as a sin-bearer, in virtue of that federal union between him and his people, which lay at the foundation of the whole. Thus God condemned sin in the flesh, and in consequence of this there is no condemnation to us.