More than Sacrament, the Cross seals God in the soul.

For the word of the cross is folly to those who are perishing, but to us who are being saved it is the power of God (1 Corinthians 1:18)

Volume 3-April 21, 1900

As I was in my usual state, or rather, with a little bit of concern about something which it is not necessary to say here, my sweet Jesus, on coming, told me: “…And they are sacred vessels, and every now and then it is necessary to dust them off. Your bodies are as many sacred vessels, in which I make my dwelling, therefore it is necessary that I do some little dusting every now and then – that is, that I visit them with some tribulation, so that I may remain in them with more decorum. Therefore, remain calm.”
Later, after I received Communion and He renewed in me the pains of the crucifixion, He added: “My daughter, how precious is the cross! Take a look: the Sacrament of my Body, in giving Itself to the soul, unites her with Me, It transmutes her to the point of becoming one with Me. But as the species are consumed, the union, truly established, ceases. Not with the cross. The cross takes God and unites Him with the soul forever, and it places itself with greater security as the seal. Therefore, the cross seals God in the soul, in such a way that there is never separation between God and the crucified soul.”