Sigh. How many times do I have to say it. Proof is a attribute of a physical world. It involves the five senses, and it can be repeated and remeasured. Spiritual events cannot be measured, and are usually not repeated. They are beyond the physical and therefore, beyond scientific proof.
Also, are you defining 'omnipotent' and 'omniscient' correctly? They mean all the power it is possible to have; all the knowledge it is possible to have. In other words, more power and knowledge than we are capable of having.
Not you, but those who question, "Is God so powerful and knowledgeable He can make a rock He cannot lift" is pure ignorance of the meaning of the words and of God.