Knowledge is not necessarily something that deepens our relationship with God. There is a distinction between the powers of intellect and will. Knowing what is good does not entail willing the good that we know. Hence, we find the good man and the man of moral science: knowing does not a good man make.
"Will follows upon intellect" is a phrase common to Aquinas and he often repeats it (seeing as it has a double-implication for man-made-in-image-of-God) -- but its significance escaped me for some time. But the idea behind it is rather simple: we must think something is good before we can pursue it. This means that there is (1) an object and (2) the subject and (3) the object affecting the subject and (4) the subject recognizing the object under the formal aspect of good and desiring it as such. Put in more basic terms: there is a lemonade stand down the street (the object). I (the subject) walk down the street one hot day and am parched from the heat and dust. I see the lemonade stand (the object affecting my sensory powers), and think "gosh, some lemonade would quench my thirst!" (the subject recognizes the good of the lemonade).
But what happens if I don't want what is good but what is EVIL? You see, I slipped The Good into the operations of will and intellect, saying that we must will something under the 'formal aspect of the good.' Aquinas states that this is because the will is the appetite for the good: the function of the will is to desire what appears to it as good (loosely speaking).
And we must have a reason for willing one thing more than another - and we will one thing rather than an other because we have weighed the options and judge one option to be better than the alternative in some respect, even if we are mistaken that x is better than y: we make a valuation.
And sometimes - often - our valuations are wrong. Ever hear of beer goggles? Well there are moral beer goggles as well. Yeah. Uh huh. So stay away from attachments to sin and bad habits!
But then there are also those who see the good, judge that the good should be done, but don't do it. St. Paul laments: "For I do not do the good I want, but the evil I do not want is what I do..." (Romans 7:19) It is God
who grants us the grace to effect the good - to be good - and Aquinas, rather bluntly, says: "It should be said that since there is no merit without charity, the act of acquired virtue cannot be meritorious without charity." (De Virtutibus 1.10, ad 4) Charity, being one of the theological virtues, is a gift. And it is the three theological virtues, poured into our souls, which enable us to not only do the good because but to know the true good as well. Wait. What? THAT'S RIGHT.
Structurally, we are created for a happiness that is beyond our nature: God wants that we should become like Him. Due to original sin, the power of the intellect was darkened and we no longer possess the ability to see and know God as the true good and, so, we can't act according to such knowledge unless we have the theological virtues infused into our souls. Faith allows us to know God as our highest good.
So, you see, knowledge does not a good man make -- but knowledge of God as the true good is necessary for salvation. And now, it is time for dinner.