From the worst of actions that one could commit is Shirk (شرك). Shirk can be of many types, like polytheism, and is one of the most vile actions and it is a must that one should stay away from it as much as possible. This article will explain some types of minor and major Shirk.
Swearing by other than Allāh is shirk. The Prophet (ﷺ) has stated that this is a wrongful act:
And he (ﷺ) also said:
ibn ʿUmar (رضي الله عنه) narrated that the Prophet (ﷺ) said:
This is one of the types of hidden shirk:
Abū Saʾīd al-Kudrī (رضي الله عنه) said:
"The Messenger of Allāh came out to us while we were mentioning the Dajjāl. and he said, 'Shall I not inform you of what I fear for you more than Dajjāl?' We said, 'Of course.' Then he said, 'Hidden shirk. That a man stands to pray, and then he beautifies his prayer for the gaze of the people watching him or the gaze of a man watching him.'" (4)
The Prophet (ﷺ) said:
"He who does good things in public to show off and win the praise of the people, Allāh will disclose his real intention (and humiliate him)." (5)
This means that saying something like "if Allāh wills and you" is Shirk, since the word "and" gathers two things together.
Abū Ḥudhayfa narrated that the Prophet (ﷺ) said:
Qutaylah narrated that a Jew came to the Prophet (ﷺ) and said:
"You are setting up rivals (to Allāh) and associating others (with Him). You say, 'Whatever Allāh wills and you will,' and you say: 'By the Kaʿbah.'" So, the Prophet (ﷺ) commanded them, if they wanted to swear an oath, to say: "By the Lord of the Kaʿbah;" and to say, "Whatever Allāh wills, then what you will."" (7)
From the worst of the types of major shirk is prostrating to other than Allāh.
ʿAbdullāh ibn Abi Awfa said:
"When Muʿādh ibn Jabal came from Syria, he prostrated to the Prophet (ﷺ), who said, 'What is this, O Muʿādh?' He said, 'I went to Syria and saw them prostrating to their archbishops and patriarchs, and I wanted to do that for you.' The Messenger of Allah (ﷺ) said, 'Do not do that. If I were to command anyone to prostrate to anyone other than Allāh, I would have commanded women to prostrate to their husbands. By the One in Whose hand is the soul of Muḥammad, no woman can fulfil her duty towards Allāh until she fulfils her duty towards her husband. If he asks her (for intimacy) even if she is on her camel saddle, she should not refuse.'" (8)
Also from the worst of the types of major Shirk is that one mocks the names of Allāh, a command from His commands, His threats, or Promises.
Rejecting that Muḥammad (ﷺ) was a Messenger of Allāh is major shirk, and this is one of the worst types of shirk to fall into.
I ask Allāh to protect us from falling into any type of shirk, and make us of the righteous.
May Allāh bless you, and shukran.
1. at-Tirmidhī 1531
2. Musnad ʾAḥmad 22980, Sunan Abū Dāwūd 3253
3. Sunan ibn Mājah 2101
4. Sunan ibn Mājah 4204, Musnad ʾAḥmad 11252, etc
5. Ṣaḥīḥ al-Bukhārī 6499, Ṣaḥīḥ Muslim 2986
6. Sunan Abū Dāwūd 4980
7. Sunan al-Ṣughrā 3773, al-Kubra 4696, etc
8. ibn Mājah 1853, al-Bayhaqī 14711, graded Ṣaḥīḥ by al-Albānī