When it comes to belief in G-d, which is by now a given based upon the first three laws that the Rambam teaches, it must be made clear that G-d Himself is absolute truth. The world is filled with a variety of truths. This is what makes people believe so many things – so many different gods. Were there to be no truth to them, they would fall apart immediately. As the Torah teaches, the letters of the Hebrew word for falsehood – 'Sheker' – are made up of three letters. 'Shin' a letter that rests upon one leg. "Kof", a letter that has only one main leg to stand upon. And 'Reish' another letter with just one leg. When it comes to total falsehood, it may possibly have a leg to stand on… but it will usually topple over in moments.
On the other hand, the Hebrew word for 'Truth' – 'Emet' – is made up of three letters of another kind. The first letter – Aleph – has two legs to stand on. The middle letter – Mem – has a complete sturdy base upon which it rests. And the third letter – Tav – likewise has two legs to stand on. Not only that, but it encompasses the entire Aleph Beit – the Hebrew alphabet. It's first letter Aleph, is the first letter of the word Emet. It's second letter Mem is the middle letter of the alphabet, and it's third letter Tav is the final letter of the alphabet. Truth can stand up to anything – because it has two strong legs with which to hold itself up and balance itself. It is also not afraid to encompass everything, because truth extends from the beginning of the matter to it's end – no matter what is included in it. It holds strong!
The sages teach that any falsehood not mixed with a little truth is destined to collapse (and fast!), but falsehood mixed with even the most minute amount of truth can still stand. This is because that point of truth mixed within the falsehood, works hard at balancing the falsehood (that cannot stand on it's own) making it appear that the falsehood is in fact truthful.
So it is that much of the falsehood of the world is believed. Those sharing this nonsense of falsehood, do so with wisdom – by including just the smallest measure of truth into things. Naturally, to the average person, the truth is so mixed within the falsehood, that nobody is the wiser to be able to distinguish the good from the bad.
As Rebbi Nachman of Breslov teaches: The reason we learn Halacha (the Jewish law) is in order to be able to learn how to separate the good from the bad. This is why the give and take of Torah learning is filled with a variety of opinions. Through the different opinions, one begins to see the situation from a variety of sides. Through the give and take – one eventually cuts away and comes to see the truth – finally brought up in a main code of Jewish law (without the give and take) such as the Shulchan Aruch.
Learning Gemara (Talmud) and other various legal texts helps to train the mind to understand how to think correctly. We live in a world mixed with truth and falsehood – a problem begun with the eating from the Tree of Knowledge - Good and Evil, when this mixture became absorbed into everything and anything. So today, there is nothing that does not include both good and bad. Our job is to be able to filter out the bad – to sort the bad from the good, to be left only with the good, only with the truth.
When it comes to G-d, however, He is absolute truth. There is nothing quite like His truth. There is nothing about Him that lies. There are no fabrications about Him. The essence of everything in the world – everything that exists, is included within the truth of G-d. Nothing can be concealed from Him – for He encompasses absolute truth and includes all truth.
Absolute truth is impossible for the average person to ever understand – though it is the ultimate goal for the serious student of Torah. The truth must be arrived at and must be practised, for this is what G-d wants from each of us.
There is nothing but G-d. He includes every possibility of truth. Everything about Him is true. There is nothing else that can compare to this truth, for everything else – no matter how good it is, still includes an aspect of ego, an aspect of a mixture of good and bad, an aspect of falsehood – no matter how far away it seems from that particular thing. Our very world is a world of falsehood, an upside down world, where "those on the top are really on the bottom, and those on the bottom are on top." The world that follows this one – the World to Come, is a world of truth, a world without the masks of our world – where everything is revealed – G-d is revealed, and with it, absolute truth, a truth that none of us can run away from.
Meanwhile, our job in this world is to acknowledge the truth of G-d, to strive for it, and to work towards the goal of making our lives filled with complete truth. We do this through the study of the Torah and the practice of the Mitzvot.