If God is real, then something must exist in our finite universe which is infinite, as infinite can only exist in the mind of an infinite God. So if we can prove that there are numbers which aren’t rational numbers and go on forever, then infinite somehow exists in our finite universe, and thus they must exist in the mind of God.

We could also examine historical claims and documents about Jesus and see if they are genuine. See if they have any inconsistencies with that time period (eg, contradict history) or correlate too perfectly or flat-out contradict each other. If they don’t then they are likely genuine. We could try and see if there is any other explanation other than Jesus rising from the dead.

If the universe was created by God, then it must have laws that are consistent and rational, so we can examine science and see if elements of this universe follow consistent patterns and have structure to them, showing that there was some form of design.