A hadith and commentary.
The Prophet, peace and blessings of Allah be upon him, said:
"Indeed, Allah forbids you from swearing by your fathers."
"So whoever must take an oath,"
"let him swear by Allah or remain silent."
'Umar, may Allah be pleased with him, said:
"By Allah, I have not sworn by them since I heard the Prophet, peace be upon him, forbid it,"
"neither as an originator nor as a narrator."
The meaning of "originator" is:
That is, speaking the words on my own initiative.
And the meaning of "narrator" is:
That is, reporting from someone else that they said it.
Commentary:
The Companions, may Allah be pleased with them, in the early days of their Islam,
used to swear by other than Allah.
They would swear by their fathers and mothers,
and they would swear by honor, honesty, and other such things.
So the Prophet, peace be upon him, forbade them from swearing by other than Allah.
'Umar, may Allah be pleased with him, was among those who heard this prohibition,
and he complied with the command immediately.
He never let an oath by other than Allah pass his lips ever again,
even when he was quoting the speech of others.
This is what is incumbent upon the Muslim:
to comply with the command of Allah with firmness and resolve,
without hesitation, procrastination, or weakness.
Among the forms of swearing by other than Allah in this day and age
is the saying of some people, "By your life,"
and their saying, "By the Prophet,"
and their saying, "By the Ka'bah."
All of this is from the forbidden types of oaths.
Indeed, it is a form of shirk (associating partners) with Allah.
We ask Allah for safety.
Ahmad, Abu Dawud, and al-Tirmidhi recorded
from 'Abdullah Ibn 'Umar, may Allah be pleased with them both,
that he heard a man say,
"No, by the Ka'bah."
Ibn 'Umar said to him,
"Do not swear by other than Allah,"
"for I heard the Messenger of Allah, peace be upon him, say:"
"Whoever swears by other than Allah,"
"has committed kufr (disbelief) or shirk."
Imam al-Tirmidhi said:
This is a hasan (good) hadith.
And Shaykh al-Albani authenticated it.