No qualification is required for worshipping the gods and goddess. If we search for a job, the employer would check for our experience, and based on that only, we would get a job. If we want to join in a school, we have to pay the prescribed fees and then only we would be allowed to join in the school. Likewise, if we want to get married, we must be employed in a good concern, and must draw a decent salary.
Apart from that, the bride’s family also would check about our whereabouts. And if they are satisfied with us, then they would proceed further. Suppose if we lose our job before marriage, then the bride’s family would even go to the extent of stopping the marriage itself.
But for worshipping the god, he is not expecting anything in return for that. He only expects a true bhakti and sincerity from us and nothing more else. Just by offering a few flowers alone would please the divine deities, and they would do wonders in our lives. Even the supreme deities would not distinguish their devotees based on caste, creed and community, and they are ready to lend their helping hands on the bad ones also.
From the ancient legend, we can understand, that how Lord Krishna had shown mercy on his sick devotee, and he even cleansed the dirt contained in the body of his devotee, and applied sandal paste on his body.
Similarly holy avatars like Ayyappan, Rama and Lord Venkateshwara had interacted with their low caste devotees, and also gave their divine vision to them. For doing all sort of these things, they are not seeing their qualification, but they are seeing only their true love with them.
Without having bhakti on the god, even if we do thulabaram to the god by offering gold equivalent to our weight, would not satisfy him, and he would not accept our precious things. Whereas if a poor devotee offers a small piece of Tulasi leaf with sincere devotion on the god, then the mighty god would immediately accept it, and would gift the most precious thing to him, that is, he would make him to attain salvation.