Is the husband entitled to refuse to give his wife the money she requested to buy something of minor importance, knowing that she is a housewife and this is the first time she has asked him, and that the amount represents one-third of what the husband owns and intended to invest in a project?

It is obligatory for the husband to spend on his wife in a reasonable manner. The obligatory spending is the amount that suffices, as is customary, taking into consideration the circumstances of both spouses. If the wife requests something beyond her obligatory maintenance, the husband is not obliged to give it to her. However, it is an act of kindness and noble character for him to give her what she requests for a permissible need, because the foundation of the relationship between spouses is affection, mercy, mutual consideration of each other's circumstances, and comforting each other.