Al-Matalib al-'Aliyah 2792 — Intellect and its virtue

It is narrated from Mujahid (may Allah have mercy on him) that I asked Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) which pilgrim to the House of Allah is the most excellent and the greatest in reward? He replied: "The person in whom three qualities come together: a sincere intention, complete intellect and understanding, and spending from lawful wealth." Then when this was mentioned to Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both), he said: "He has spoken entirely the truth." I said: If the intention is sincere and the wealth is also lawful, what harm will a lack of intellect do him? He said: "O Abu al-Hajjaj! You are asking me the same question that I asked the Messenger of Allah (peace and blessings be upon him), and he (peace and blessings be upon him) said: 'By the One in whose hand is my soul! The servant has not obeyed his Lord with anything, neither with jihad nor with any other kind of righteousness, until he understands it with his intellect and awareness. And even if an ignorant person, with his intellect, were to surpass those who exert themselves to the utmost in worship, the corruption he causes would still be far greater than the good he does.'"
The chain of this report contains Abd al-Wahhab bin Mujahid, a lying and matruk (abandoned) narrator, because of which this hadith is very weak and unreliable.