And as for the second: it is the hadith of Aisha that the Prophet (peace and blessings be upon him) said: Whoever vows to obey Allah, let him obey Him.

The Shaykh : And as for the second: it is the hadith of Aisha that the Prophet (peace and blessings be upon him) said: : A vow is when a person obligates himself to do something for Allah (Mighty and Majestic), such as saying: I have a vow upon me for Allah to fast, to pray, to recite the Qur'an, to give charity, to perform Hajj, to perform 'Umrah, and the like of that.
And a vow is either forbidden or disliked: some scholars hold that a vow is forbidden, and that it is not permissible for a person to make a vow, because he burdens himself with what he has no need for. How many people have vowed and not fulfilled it, how many have vowed and struggled in fulfilling it, and how many have vowed and gone to the doors of scholars seeking their rulings, hoping to find a dispensation.
So the important point is that the Prophet (peace and blessings be upon him) prohibited vows, and the scholars of the Muslims differed regarding this prohibition:
Some of them said it is for prohibition, and some of them said it is for dislike.
But if one vows to obey Allah, it is obligatory for him to obey Allah as an obligation. So if he says: I have a vow upon me for Allah to fast every Tuesday of every week, it is obligatory for him to fast every Tuesday, and it is not permissible for him to escape it, except for an excuse such as illness or the like.
And if he vows to pray two rak'ahs for Allah in the Dhuha prayer every day, it is obligatory for him to pray two rak'ahs.
And if he vows to give charity of one hundred dirhams, it is obligatory for him to give charity necessarily, even though he was free from that. A person, if he wishes, gives charity, and if he wishes, he does not give charity; and if he wishes, he fasts, and if he wishes, he does not fast; and if he wishes, he prays, and if he wishes, he does not pray, in matters other than the obligations of Allah. So he is in freedom and ease, but he goes and tightens things upon himself.
And the wonder is that some people—we ask Allah for guidance for us and for them—when they are sick, they say: I have a vow upon me for Allah, if Allah heals me, I will certainly do such and such. Glory to Allah!! Allah does not heal you except if you give the condition. For this reason, the Prophet (may Allah pray upon him and grant him peace) pointed to that and said: : If Allah wills a matter, whether you vowed or did not vow, it will be completed.
And he said: : And the truth is, upon him (may Allah pray upon him and grant him peace), there is no good in a vow. How many people have vowed and not fulfilled it.
And know that if you vow on a condition and do not fulfill it when the condition is met, then you are threatened with a great matter, threatened with hypocrisy that Allah will place in your heart until you die. Allah the Exalted said: : Look, they covenanted with Allah : meaning He gave us wealth so we will give from the wealth, : so we will stand by the obedience of Allah , and their desire was fulfilled for them and they did not give charity, , and they were not among the righteous. They did not fulfill what they covenanted with Allah, : permanent hypocrisy from which they are not successful in repenting, and their hearts do not shed it, but rather the hypocrisy remains in their hearts until they die, and refuge is sought in Allah, and they die upon hypocrisy. Why? He said: from the charities : from their saying that we will be among the righteous.
So the important point, O my Muslim brother, is to beware of vows and warn your Muslim brothers. Say to the sick person: If Allah wills healing for you, He will heal you without a vow. Say to the student: If Allah wills that you succeed, you will succeed without a vow. Say to the one who lost something: If Allah wills to bring it to you, He will bring it to you without a vow. And fear Allah in yourself. If that thing happens, then at that time, thank Allah, give charity as you wish, fast, pray.
As for making a vow as if Allah the Exalted does not bring good except if a condition is set for it, we ask Allah for safety. For this reason, the statement of prohibition is a strong statement, the prohibition of vows, and to this leaned Shaykh al-Islam Ibn Taymiyyah (may Allah have mercy on him).
: If he vowed to drink intoxicants, for example, it is forbidden for him to drink intoxicants, and it is not permissible for him to drink intoxicants by vow. He does not say: I vowed, I will fulfill my vow. We say: There is no fulfillment of a vow in disobedience to Allah. If he vowed to transgress against a person, it is not permissible for him to transgress against him even if he vowed. If he vowed to backbite a person, it is not permissible for him to backbite him. If he vowed to cut off ties with his relative, it is not permissible for him to cut off ties with his relative. If he vowed to be undutiful to his parents, it is not permissible for him to be undutiful to his parents, because that is disobedience: : But what does he do? The scholars said: He does not disobey Allah and expiates with the expiation of an oath. He feeds ten poor people, or clothes them, or frees a slave. If he does not find, he fasts three consecutive days, based on a hadith that came regarding that from the Prophet (peace and blessings be upon him).