(And indeed We showed him (Fir`awn) all Our Ayat, but he denied and refused.) This means that the proofs, signs and evi- dences were establi- shed against Fir`awn and he saw them with his own eyes, but he still denied and rejec- ted them due to his disbelief, abstinence and transgression. This is as Allah, the Exalted, says,

(And they belied them wrongfully and arrogantly, though they themselves were convinced thereof.) ﴿27:14﴾

(57. He (Fir`awn) said: "Have you come to drive us out of our land with your magic, O Musa'') (58. "Then verily, we can produce magic the like thereof; so appoint a meeting between us and you, which neither we nor you shall fail to keep, in an open place where both shall have a just and equal chance.'') (59. (Musa) said: "Your appointed meeting is the day of the festival, and let the people assemble when the sun has risen (forenoon).'')