What is the ruling concerning groups that spend four months and forty days in various parts of the earth inviting Muslims to adhere to the commands of Sharia?

Jama'at al-Tabligh is a group working for Islam, but it has some observations and errors, including: not adopting the creed of Ahl al-Sunnah (definition) wal-Jama'ah, their lack of interest in Islamic knowledge, interpreting verses in a way that does not conform to their meaning, making the arrangement of going out for da'wah an act of worship, and their involvement in Islamic violations such as making one of their men supplicate and attributing their success to him, the spread of weak and fabricated hadiths among them, and their not speaking about evil deeds. Some of them also fall into self-admiration and arrogance, and they consider going out for da'wah better than other acts of worship, and some of them dare to issue fatwas, interpret, and narrate hadith (definition) without knowledge, and some of them neglect the rights of their children and wife. Therefore, scholars have not permitted going out with them except for those who have knowledge and insight to correct their mistakes and advise them, as Sheikh Ibn Baz and Sheikh Al-Fawzan emphasized.