Bukhari

Hadith Commentary:
In this hadith, there is mention of a generous man from the Children of Israel who, with the intention of distributing charity (sadaqah and khayrat), went out at night. However, unknowingly, on the first night he placed his charity in the hands of a thief, on the second night he gave it to an immoral woman, and on the third night he gave it to a wealthy person who was not deserving.
All of this happened unknowingly.
Later, when these incidents became known to him, he acknowledged his ignorance and praised Allah, as if he said:
اللهم لك الحمد أي لا لي أن صدقتي وقعت بید من لا یستحقها فلك الحمد حیث کان ذلك بإرادتك أي لا بإرادتي فإن إرادة اللہ کلها جمیلة۔
That is, O Allah! Praise is for You alone, not for me.
My charity reached the hands of one who was not deserving, so praise is for You alone.
Because this happened by Your will, not by my will, and whatever Allah wills and intends is always best.
The purpose of Imam Bukhari in this chapter is that in such circumstances, even though the charity reached a non-deserving person, it was still accepted by Allah.
This is also evident from the hadith, that if, out of unawareness, charity is given to a non-deserving person, Allah still accepts it and the giver receives reward.
The word "sadaqah" includes both voluntary charity (nafl sadaqah) and obligatory charity (zakat).
The generous man from the Israelites was informed in a dream, or a hidden voice (hatif ghayb) gave him the news, or the prophet of that time told him that perhaps those non-deserving recipients to whom you mistakenly gave charity may take heed from this charity and refrain from their wrongdoings.
The thief may stop stealing, the immoral woman may desist from adultery, and the wealthy person may himself be encouraged to spend in this way.
In such cases, your charity can become a great source of reward and recompense for you.
This is what is meant.

Hadith Commentary:
(1)
From the style of this hadith, it is understood that the charity was specifically allocated for the needy among the righteous people, which is why the people were astonished.
It is also understood from this that if the one giving charity is sincere and his intention is good, then his charity is accepted by Allah even if it does not reach its intended recipient.
The hadith does not clarify whether the charity was obligatory (fard) or voluntary (nafl), nor whether it would suffice or not.
Most likely, Imam Bukhari rahimahullah also, for this reason, did not adopt a decisive tone in the chapter heading but rather presented it in the form of a question.
In our view, the word "charity" (sadaqah) in the hadith includes both obligatory and voluntary charity.
In such circumstances, even if the charity reaches a non-deserving person, it is still accepted by Allah.
This means that if, out of ignorance, charity is given to a non-deserving person, Allah accepts it and the giver receives reward for it; in fact, in such cases, it becomes a cause for even greater reward.
There is no need for the one who gave the charity to give it again.

(2)
From this hadith, the importance and virtue of sincerity and giving charity secretly becomes clear.
The one who gave charity praised Allah, meaning: there is no praise for me in giving charity to an adulteress and a thief, because giving charity to them happened only by Your will and decree, even though it was not my intention; nevertheless, whatever happened, happened by Your will, and every one of Your decrees is good, so You alone are worthy of praise.