On the eve of Shabbat, when it began to darken, Rabbi Shimon ben Yochai and his son R. Eleazar saw an old man holding two bundles of myrtles in his hand, running in the twilight. They asked him:

Why do you carry these?

He told them:

In honor of the Shabbat.

'But one would be ample?'

'One for 'remember' the Shabbat and one for 'guarding' the Shabbat.

Rabbi Shimon told his son:

Behold, how dear the commandments are to Israelites.