Each individual person can do nothing better than to find and use the best epistempology (a method for determining truth) for which he or she has the resources to use it. As this will return the best possible results, while even better but utopic epistemologies return no results at all.
Therefore, people in ancient cultures (before using exact science was possible in societies, because of economic restrictions) could do nothing better than to employ historic documents, traditions and faithful witnesses to determine the truth about God. The same applies to developing countries today.
Also today, as and as long as an individual has no practical access to using scientific methodology when it comes to questions about God, the best thing is to apply the ancient’s epistemology. It’s not as good, but at least can be maintained by an individual person.
Which means: as long as I cannot execute my Second Acts project (to quasi-empirically collect facts about God’s contemporary activity), I should (and also I am epistemically allowed to) believe in Jesus Christ because of history, traditions and own (not exactly recorded) experiences alone.