The Fellowship of the Ring by J.R.R Tolkien (Harper Collins 1991) pp.236-239
It was the Elven-smiths of Eregion who gave Sauron the knowledge that he required to forge the One Ring. It was not that Celebrimbor was an ally to Sauron in his desire for the mastery of Middle-earth but that and his co-workers failed to perceive the true motives of the one they knew as Annatar. At this stage of his career Sauron was able to appear in a fair guise. That is one reason why Celebrimbor was deceived. But much more importantly he was deceived because of what he shared in common with the one who would become his deadly foe. He like Sauron had an eagerness for knowledge and this is what lead to his ultimate ensnaring.
Or so Tolkien the narrator relates that Elrond affirms in his speech to the Council in Rivendell. And I think that we must assume that Tolkien agrees with what Elrond says here for in saying this Elrond confirms the way in which the story of Sauron is told throughout the legendarium, the complete works of Tolkien regarding his mythical world. Sauron is always presented as a character who desires order and control above everything and what is always necessary if anyone is to achieve order is to possess knowledge. Without the possession of knowledge order is an impossibility.
It was th desire for order that led Sauron first to admire Melkor who was to become Morgoth and then to follow him. After the Fall of Thangorodrim and the judgement of Morgoth by the Valar Sauron was at first willing to submit to the overwhelming logic of a greater power. At least he was willing in theory. The Valar demanded that he present himself in person in Valinor in order to receive their judgement but he never came. Was this because this presentation of himself was to be a voluntary act on his part and not one that would be brought about by force? And was his ever hardening rebellion caused (in his own mind at least) by the realisation that the Valar would never enforce their will upon Middle-earth? I think that we have to affirm that the answer to both of these questions is a resounding yes.
For Sauron the patience of the heavenly beings, the Valar to whom the One entrusted the rule of Arda (the earth) at the beginning of time was a sign of the frailty of divine lordship. For most of the second and the third ages of Arda it seemed as if the Valar had little interest in Middle-earth, leaving it more or less to its own devices. The only realities that Sauron perceived were the power of Númenor and of the great Elven kingdoms of Middle-earth. Of course he fully came to understand that there was a limit to his power when he encouraged Númenor to invade the Deathless Lands and so brought down upon himself the wrath of Illuvatar but nothing changed his mind about the apparent indifference of the Powers to Middle-earth. After all what d he did perceive in order to change his mind apart from the Eagles of Manwë, Lord of the Valar, and the arrival of the Istari, the wizards, most of whom proved either to be ineffective or open to corruption?
But what of Celebrimbor and the Elven-smiths of Eregion? In what way can we say that they too shared at least something of Sauron’s perception of reality? In what way did this perception enable Sauron to ensnare them? Firstly we have to say that Sauron fully owned his perception whereas Celebrimbor did not do so. Thus one was the ensnarer while the other was ensnared; and second is that the Noldorin smiths ruled by the grandson of Fëanor also desired knowledge in order to achieve control and in their case this meant a control that would enable the preservation of beauty. Sauron may have desired mastery and order for their own sake and he may have had no interest in the preservation of beauty but in his belief that the knowledge that Sauron was offering him could enable him to preserve the beauty of an ordered world Celebrimbor proved himself a fellow traveller to Sauron’s world view.