Hastiness leads to tremendous harm…

Sheikh ‘Abdul-‘Azeez Ibn ‘Abdullah Ibn Baaz, may Allaah have mercy upon him, said,

‘“…I advise them with concern for the call to Allaah, enjoining the good and forbidding wrong with wisdom, excellent behavior, and good speech. They should proceed not with harshness and severity, but rather with gentleness and insight, as Allaah, Glorified and Exalted says, ﴾Invite (mankind, Oh Muhammad) to the Way of your Lord (i.e. Islaam) with wisdom (i.e. with the Divine Inspiration and the Qur’aan) and fair preaching, and argue with them in a way that is better.﴿-(Surah an-Nahl:125). And He, Glorified be He, said, ﴾And by the Mercy of Allaah, you dealt with them gently. And had you been severe and harsh-hearted, they would have broken away from about you. ﴿-(Surah Aal-‘Imraan:159)

I advise them to avoid hastiness in every matter. Rather, they should ascertain matters carefully, consult others, and cooperate upon goodness until they understand the religion properly, as the Messenger, may Allaah’s praise and His salutations be upon him, said, {The one whom Allaah intends good for He gives him understanding in the religion} ¹.
Indeed hastiness leads to tremendous harm. Thus, it is an obligation to verify matters and give attention to the Sharee’ah evidences, and to always frequent the sittings of knowledge of those people of knowledge well known for their uprightness and sound beliefs.’

(From Collection of Rulings and Various Statements’: Vol. 6, Page 232) ² 

1. Narrated in Saheeh al-Bukhaaree: 71, 3116, 7312/ Saheeh Muslim: 1037/ Sunan Ibn Maajah: 221/ al-Muwatta Maalik: 1300, 1667/ & Musnad Imaam Ahmad: 16395: 16404, and other than these two/ Musannaf Ibn Abee Shaybah: 31792/ & Sunan ad-Daaramee: 224, 226/ – on the authority of Mu’aweeyah. And it is found in Jaame’ al-Tirmidhee: 2645/ Musnad Imaam Ahmad: 2786/ & Sunan ad-Daaramee: 270, 2706/-on the authority of Ibn ‘Abbaas. And it is found in Sunan Ibn Maajah:220/ & Musannaf ‘Abdul-Razzaaq: 30851/-on the authority of Abu Hurairah. It was declared authentic by Sheikh al-Albaanee in Saheeh al-Aadab al-Mufrad: 517, Silsilat al-Hadeeth as-Saheehah: 1194, 1195, 1196, Saheeh at-Targheeb at-Tarheeb: 67, as well as in other of his books. Sheikh Muqbil declared it authentic in al-Jaame’ al-Saheeh: 9, 3123, 4650, may Allaah have mercy upon them both.
2.  Translated by Abu Sukhailah Khalil Ibn-Abelahyi