...if you 'pray', this language apparently does not have the word, if you - think about a god, in the direction of a god, and think about how your purposes is shared with their purposes, and ask to be made a 'cleric' by them, then sometimes - in 1% of the population - you will feel the god reach back and respond, marking you as theirs. You can feel their presence, when that happens. Gods cannot communicate even with their 'clerics' unless they spend some limited-god-resource to send you a vision, which will probably leave you with a massive headache for a day if you're lucky. This happens maybe once a year to anybody in Cheliax.
Gods grant spells to their chosen, who pray for them at dawn. Those more favored by their gods, more attuned to them and in sympathy with them, of longer and greater service, receive more powerful spells. Iker Ebogar, then, is a cleric favored enough of Employer Asmodeus to receive seventh-circle cleric spells from him, of which there are 10 such in Cheliax, and one ninth-circle, Aspexia Rugatonn.