CHAPTER No: 12
To vow to other than Allah is an act of Shirk
Allah the Most Exalted said:
"They (are those who) fulfill (their) vows, and they fear a Day whose evil will be wide-spreading."
Allah the Most Exalted also said:
"And whatever you spend for spendings (e.g. in Sadaqah charity etc. for Allah's cause) or whatever vow you make, be sure Allah knows it all."
Narrated 'Aishah (May Allah be pleased with him) that Allah's Messenger (May the peace and blessing of Allah be upon him) said:
"Whoever vows that he will be obedient to Allah, he should be obedient to Him; and whoever made a vow that he will disobey Allah, he should not disobey Him".
Important issues of the Chapter
1) Fulfillment of the vow is obligatory.
2) Since it is approved that making a vow is an act of worship to Allah, then directing a vow to other than Allah is committing Shirk.
3) Any vow based on disobedience (to Allah the Almighty) is impermissible to be carried out.