Slaves are significantly excluded by the halakhah (Jewish law)
from three aspects of Jewish life. They are:

1. pasul le’edut – a slave is disqualified from giving testimony in court;
2. patur mimitzvot aseh shehazeman geraman – … he is exempt from performing such positive commandments for which a particular time has been set; and
3. issur hitchatnut – a slave may not marry, and thereby bind himself to another, while he is still a slave…

Mitzvot aseh shehazeman geraman.
A slave is relieved of the requirement to observe time-related mitzvot
because he lacks time-consciousness…
The only creature that can experience time, that feels its passage
and senses its movement, is man.
This is called time-awareness…

Time-awareness is the singular faculty of the free man,
who can use or abuse it.

To a slave, it is a curse or a matter of indifference.
It is not an instrument which he can harness to his purposes.

The free man wants time to move slowly
because, presumably, it is being employed for his purposes.

The slave may want to accelerate time,
because it will terminate his oppressive burdens.
Not being able to control time, the slave grows insensitive to it;
inexactitude and unawareness characterize his schedule…

||Joseph B Soloveitchik (1903–1993), (Edited by Abraham Besdin), 1979 ||