Are the books Bihaar al-Anwaar and Tafseer al-Jalaalayn trustworthy?

Firstly: 

The book Bihaar al-Anwaar by Muhammad Baaqir al-Majlisi is one of the books of the Raafidi Shi‘ah. In fact it is an ocean (bihaar) filled with fabrications and misguidance for which there is no known basis or foundation, apart from the false, innovated religion of the Raafidis. 

Secondly: 

With regard to Tafseer al-Jalaalayn (by Jalaal ad-Deen as-Suyooti and Jalaal ad-Deen al-Muhalli), it is a good tafseer and summary, but it is not free of some shortcomings, especially with regard to the attributes of Allah and matters of ‘aqeedah (belief), in which it follows the madhhab of the Ash‘aris. In that regard you may benefit from reading the book Anwaar al-Hilaalayn fi at-Ta‘aqqubaat ‘ala al-Jalaalayn, by Dr. Muhammad ‘Abd ar-Rahmaan al-Khamees. 

Shaykh Ibn Baaz was asked about that and he said: It is a useful tafseer, although it contains some errors regarding the divine attributes… There is hardly any book that is free of errors, except the Book of Allah. Books written by people usually contain some errors, but some have fewer errors than others. Tafseer al-Jalaalayn contains some errors, so if it is possible to be taught it by one who has knowledge of the Sunnah and knows the views of Ahl as-Sunnah wa’l-Jamaa‘ah, and he can alert his students to the mistakes, that is good. If a student does not understand something, he should ask the scholars.

End quote from the Shaykh’s website:

http://www.binbaz.org.sa/mat/10505 

For a detailed biography of Imam as-Suyooti, please see the answer to question no. 10383 

And Allah knows best.