Is there a logical problem?

I had an argument with a friend regarding the words of the Chabad Rebbe, and I would be happy to hear your opinion.
Regarding the ‘degree of security’, the Chabad Rebbe wrote as follows:
“The duty of security that we are commanded to have is not just a detail and a result of the belief that everything is in the hands of Heaven and that God is gracious and merciful, so that there is no need for a special obligation for it. Rather, this duty is a work in itself, the essence and definition of which is that a person trusts and relies on God, until he casts his entire fate on the Lord, as the saying goes, ‘Cast your fate on the Lord your God,’ for he has no support in the world without Him.”
And it must be said that this is what is meant by what he wrote in the Obligations of the Hearts that security is “like a captive slave who is in the house of a fool under the authority of his master,” that the prisoner’s entire security is only in his master, who “has delivered him into his hand, and no one can harm him or benefit him, etc.” except him.
According to the words of the Chabad Rebbe, the meaning of “certainty” is that the Creator will certainly do good to man (and not as the well-known words of the Chazo”a). To this the question arises: Who said? Where does the certainty come from that the Creator will only do good for man? Perhaps he has sins, etc., etc.
The Rebbe explains further:
“And this in itself is the basis for a person’s confidence that God, the Holy One, will benefit him with visible and manifest goodness, even if he is not a witness to this grace:
The meaning of confidence is not that one believes that since God’s grace is without measure and limitation, whether for the deserving or the undeserving, therefore he will receive God’s grace without any work on his part (because according to this, the whole matter of reward and punishment is nullified) – but confidence is work and achievement in one’s soul, and it brings God’s grace that comes as a result of one’s work and achievement to trust in God. By a person truly and deeply trusting in his soul only in God alone, to the point of not worrying at all, then this awakening itself works, that God acts with him in this way, which is beneficial to him (even if otherwise he would not deserve it).”
So much for the Rebbe’s words. One may disagree with the very explanation given for many reasons. I will not go into that, I am merely asking whether there is a logical problem with this proposal in the following respect:
In fact, is he confident that he will be well – what is the justification that it will really be so – the very effort of a person to internalize that he will be well. Is this acceptable? Can a person be sure that there will be a table here, since they told him that if he is confident, there will indeed be a table here?
What do you think? Is this a logical problem?