I am currently reading The Silmarillion and am about 225 pages in right now, reading about the Silmarils and the lies of Melkor.
One thing that perplexs me; When Melkor was set free and brought before Manwe for pardon, he could not sense the evil and lies within him. Melkor then goes on to poison the minds of the Noldor and the House of Finwe against each other. It is said that only Tulkas and Ulmo saw through his lies.
Why is this? Manwe who is supposedly the 'King' of the Ainur, cannot see Evil in Melkor's heart? Are the Ainur not the most powerful beings in on Ea, second only to Iluvatar himself?