Allah, the Almighty, said:

{…and We would certainly have made confused to them what they make confused.}⁸⁰⁸ [al-An‘âm 6:9]

At-talbeesis to cover an extant being with a borrowed indicant. It is of three meanings:

The first is the Real confusing the people of dispersion by the universe, and this is by attaching the extant events/things to the causes, places, and times; and His attaching the realizations to the means, the facts to the proofs, the rulings to the effective causes, the retribution to the offenses, and the reward to the acts of obedience. He hides the pleasure and anger that warrant the detachment and connection and that bring to fruition suffering and happiness. ⁸⁰⁹

The second confusion is when the people of ghayrah (protectiveness) cover up the times (of good deeds) and the karâmât (supernatural gifts) by concealing them,⁸¹⁰ their confusing others by [engaging with] earnings and causes, and the attachment of phenomena to the indicants and triggers to confuse the feeble eyes and flawed intellects, while perfecting their ascertainment in belief and practice;⁸¹¹ this group is a mercy from Allah for the people of dispersion and causes when they mingle with them. ⁸¹²

The third confusion involves the people of establishment confusing the people out of mercy for them by engaging with the causes and to bring ease and facility to the people, not to themselves; this is the degree of the prophets, and it is for the godly imams who come from the valley of union and point to its essence. ⁸¹³

⁸⁰⁸ In Madârij, Imam Ibn al-Qayyim found the verse unsuitable for the subject. Here is the larger context of it:

{And they say: Why was there not sent down to him an angel? But if We had sent down an angel, the matter would have been decided; then they would not be reprieved. * And if We had made him an angel, We would have made him [appear as] a man, and We would certainly have made confused to them what they make confused.} (al-An‘âm 6:8-9)

It is a conditional statement to explain why Allah did not send angels as messengers. People would have no power to receive directly from them in their angelical form. If they were made to come in a human form, the people would have still been confused about them. In general, Allah sent clear (mubeen) messages and messengers; He does not wish to confound His creatures.
⁸⁰⁹ All of this should be understood within the context of this life being a test. If all the realities were to be made manifest to people, there would not be a test. Some phenomena conceal the noumena (realities) behind them from those who have lack of insight. It is important here to point out that the correct position among Ahl al-Sunnah is that causes have power inculcated into them by God to lead to their effects. However, He has ongoing creation, ownership, and control of the causes, effects, and the causal relationship itself.
⁸¹⁰ They hide their good deeds and they hide any karâmât they receive from God unless there is a superior benefit in disclosing them, such as to support the believers and strengthen their resolve in times of distress and hardship.
⁸¹¹ While engaging with all the causes, they are certain of Allah’s ultimate control and have complete reliance on Him.
⁸¹² Despite the sublime condition of their interiors, their exteriors are not very different from the people, making it easy for them to benefit from their company.
⁸¹³The sheikh may have meant that the messengers and the vanguard among the pious servants engaged with the causes only to facilitate things for people, while they knew they had no utility (fire does not burn, water does not quench, knives do not cut, etc.). Allah is in control of all things, and whether or not you engage with the causes, there will come to pass only what Allah had already decreed. If this is, in fact, what the sheikh meant, then it is problematic. The messengers came to teach us what is right, not to confuse us but to lead us to our wellbeing in this life and salvation in the hereafter. Engaging with the causes Allah made as means to the desired ends is what is required of us. If we are hungry and refrain from eating until we die, we would be liable in His sight. Engaging with them does not compromise our faith in His control and power. It is an obedient response to His instruction. The formula is perfect and simple. Anas ibn Mâlik narrated that a man asked (concerning his camel):O Messenger of Allah! Shall I tie it and rely (upon Allah), or leave it loose and rely (upon Allah)?
He said: (اعْقِلْهَا وَتَوَكَّلْ‏) Tie it and rely (upon Allah). (at-Tirmidhi, graded ḥasan)
This is what the Prophet ﷺ consistently did. The migration from Makkah to Madinah is the epic example of the perfect mixing of engaging with the causes and reliance on Allah.