marriage to the adopted sons divorced wife

[samina]

33.37 And when you said to him to whom Allah had shown favor and to whom you had shown a favor Keep your wife to yourself and be careful of (your duty to) Allah; and you concealed in your soul what Allah would bring to light, and you feared men, and Allah had a greater right that you should fear Him.
But when Zaid had accomplished his want of her, We gave her to you as a wife, so that there should be no difficulty for the believers in respect of the wives of their adopted sons, when they have accomplished their want of them; and Allah's command shall be performed

this verse is quite disturbing to me , why does Allah almighty want prophet muhammed to get married to zaids divorced wife just because he wants tht there should be no doubt in believers mind in regard of getting married their adopted sons divorced wife , he could just tell clearly in quran tht u can gett married to ur adopted sons divorced wife .