THE SAME NUMBER OF DAYS.
And that is why Jesus fasted when he was tempted, when he was still in need of food before his death. Although he ate and drank when he was glorified, he was not in need of food after his resurrection.[1] On the first occasion, you see, he was demonstrating in himself our pain. On the second he was demonstrating in us his consolation.[2] Both instances occurred within a period of forty days. I mean, he fasted for forty days, when he was being tempted in the desert, as it is written in the Gospel, before his death in the flesh;[3] and again he was with the disciples for forty days, as Peter puts it in the Acts of the Apostles, going out and coming in, eating and drinking[4] after his resurrection in the flesh.
This number forty seems to signify the course of this age in those who are being called to grace, through the one who did not come to undo the law but to fulfill it.[5] There are, after all, ten commandments of the law, now spread by the grace of Christ throughout the world (and the world is four-cornered, and ten multiplied by four makes forty); since those who have been redeemed by the Lord, from the regions he has gathered them together, from east and west and north and the sea.[6] And so by fasting for forty days before his death in the flesh, it is as though he was crying out, Hold yourselves in check from the desires of this world; while by eating and drinking for forty days after his resurrection in the flesh, it is as though he was crying out, Behold, I am with you until the end of the world.[7]
Sermon 263a.4