Its called the null hypothesis. Unless you have evidence to the contrary the default position should be that life comes from other living things only.
That is not the null hypothesis, actually. You don't understand the terms you are using.
The null hypothesis is that the independent variable being studied has no effect on the dependent variable. The actual null positions here are that neither life nor non-life can create life. We have evidence that life can create other life, and so far do not have concrete evidence that life can arise from non-life.
In no way does that make that life can ONLY come from other life the default position. That would be a profound misunderstanding of science.
Not to mention that if that's the case God has the same problem. That is unless you just magically declare it not a problem, which then leaves you in absolutely no position to criticize anyone else because you've abandoned logic.
There is simply no problem with evolution or the origin of life that is not an even larger logical problem for theistic creation.