Rabbi Moshe Hagiz, in his book Mishnat Chachamim, writes that he heard this story from reliable people in Safed who were there when it happened.

In the mid-16th century, a converso Jew from Portugal moved to the holy city of Safed. Deprived in his youth of the opportunity to practice the religion of his fathers openly, he was overjoyed to finally be able to do.

Years later, he heard a talk by the rabbi of the synagogue he attended about lechem hapanim, the “showbread” which was offered in the Holy Temple each Shabbat (see Leviticus 24:5–9). After discussing the various laws and procedures governing the preparation of this offering and touching on its mystical significance, the rabbi bemoaned the fact that, because of our sins, we no longer have this ready means to propitiate G‑d.

The Jew took these words to heart. When he arrived home, he asked his wife to prepare two special challahs on Friday. He related to her all the details he remembered from the lecture on the showbread. She should sift the flour thirteen times, knead it while she was in a state of ritual purity, and bake the dough very well in their oven. He told her that he wished to present these loaves as an offering to G‑d; hopefully He would consider them an acceptable sacrifice and eat them.

His wife loyally fulfilled his request, and early that Friday afternoon, when no one was likely to be in the synagogue, the man brought the loaves there under his cloak. He prayed and cried that G‑d should look upon his offering with favor, and eat and enjoy the lovely, freshly baked bread. He went on and on, like an errant son begging his father for forgiveness. Then he placed the loaves, wrapped, in the Holy Ark, beneath the Torah scrolls, and quickly left for home.

The shamash (caretaker) of the synagogue arrived later that day to complete preparing the shul for the holy Shabbat. One of his duties was to check that the Torah scroll was rolled to the proper place for the reading the next morning. When he opened the Ark, he was surprised to see that a package had been neatly placed inside. He opened it, and there were two fine-looking challah loaves! He had no idea where they had come from, but he didn’t think too much about it; he simply decided to take them home and eat them—after all, they looked and smelled delicious!

And they were delicious. The caretaker was delighted with this unexpected fringe benefit of his job.

That evening, the Jew waited impatiently for the end of the prayers. When everyone had left the synagogue, he approached the Ark in great trepidation and swung open its doors. The loaves were not there! He was so happy. He hurried home to share his joy with his wife. He innocently proclaimed that G‑d had not disdained the poor efforts of such insignificant people as themselves. Indeed, He had accepted their two loaves, and eaten them while they were still warm!

“Therefore,” he exhorted her, “let us not be lazy, for we have no other way to honor Him, and we see that He loves our bread. Every week we must try to give Him this pleasure with the same care and devotion that we did this first time.”

His wife was swayed by his wholehearted excitement, and gladly cooperated. Every Friday morning she faithfully prepared two beautiful loaves, paying careful attention to every detail, great and small, and every Friday afternoon he delivered them to the synagogue, and earnestly prayed and pleaded with G‑d for their acceptance.

And every Friday the caretaker would come along and happily eat the delicious challahs. And every Friday night the Jew from Portugal ecstatically informed his wife that once again their meager offering had been accepted.

So it went, for many weeks and months.

One Friday, the rabbi of the synagogue stayed much later than usual, until the afternoon. It was the same rabbi who had given the speech about the “showbread” that had so inspired the converso from Portugal. He was standing on the bimah (reading platform), reviewing the sermon he planned to give the next day, when, to his surprise, he saw one of his congregants enter carrying two loaves of bread, walk up to the Ark, and deposit them inside. He realized that the man was unaware of his presence, and he heard him utter fervent prayers for G‑d to accept his offering and enjoy the challahs.

The rabbi listened in astonishment. At first he was silent, but as he began to understand what was going on, his anger rose. Finally he was unable to restrain himself any longer, and burst out in fury: “Stop! You fool! How can you think that our G‑d eats and drinks? It is a terrible sin to ascribe human or any physical qualities to G‑d Almighty. You actually believe it is the L‑rd who takes your measly loaves? Why, it is probably the shamash who eats them.”

At that moment the caretaker entered the synagogue, blithely expecting to pick up his challahs, as usual. He was a bit startled to see the rabbi and another man standing there. The rabbi immediately confronted him. “Tell this man why you came here now, and who has been taking the two challahs he has been bringing each week.”

The caretaker freely admitted it. He wasn’t embarrassed at all. He couldn’t understand why the rabbi was so agitated, and why he was yelling at the other man, who looked so unhappy, whom he knew to be an unlearned but sincere Jew.

As the rabbi continued his rebuke, the man burst into tears. He was crushed. Not only had he not done a mitzvah as he had thought, it seemed he was guilty of a great sin. He apologized to the rabbi for having misunderstood his lesson about the showbread, and begged him to forgive him. He left the shul in shame and despair. How could he have been so wrong? What was he to do now?

Shortly thereafter, a messenger from the “Holy Ari,” Rabbi Yitzchak Luria, strode into the synagogue and approached the rabbi. In the name of his master, he told the rabbi to go home, say goodbye to his family, and prepare himself: by the designated time for his sermon the next morning, his soul would have already departed to its eternal rest. Thus it had been announced from Heaven.

The rabbi couldn’t believe what he had just heard, nor could the disciple explain it to him. So the rabbi went directly to the Ari, who confirmed the message and added, as gently as possible: “I heard that it is because you halted G‑d’s pleasure, the likes of which He hasn’t enjoyed since the day the Holy Temple was destroyed. That is what He felt when this innocent converso would bring his two precious loaves to your shul each week, faithfully offering them to G‑d from the depths of his heart with joy and awe, and believing that G‑d had taken them, until you irrevocably destroyed his innocence. For this the decree was sealed against you, and there is no possibility to change it.”

The rabbi went home and told his family all that had transpired. By the time of the sermon the next morning, his soul had already departed to hear Torah in the Heavenly academy, exactly as the Ari had said.

Biographical note:
Rabbi Yitzchak Luria (1534–1572), known as “the Holy Ari,” revolutionized the study of Kabbalah and its integration into mainstream Judaism during the two years he spent in Safed before his passing at age 38.