How can I be assured that Christianity is correct and the one true way?

The only way you can be sure is to ask the hard questions. Whether or not
Christianity is the true and correct way hangs on whether the Bible is
inspired by God. And assuming this whether you are following that correct
way depends on how carefully you are studying and following what the Bible
teaches. In 2Tim 3:16,17 it is claimed that all Scripture (the Old and by
implication the New Testament as well) is inspired by God. This claim is
either true or it is not. If this claim holds up to the evidence and to
careful examination, and if you are following carefully and accurately the
teachings of the Bible, they your “Christian faith is correct and the one
true way.”

There are no short cuts. You will have to ask the hard questions and do
the research until you have satisfied yourself that the Bible is truly
inspired by God. Of course, this web site is filled with articles intended
to prove exactly that. I would recommend my book “Reasons for Belief: A
Handbook of Christian Evidences” as it contains in one fairly compact and
hopefully readable book a summary of most of the basic evidence in support
of the claim that the Bible is inspired by God. If you do not have a copy,
it is available for puchase at this website.

The next question is whether or not you are following that faith “once and
for all delivered to the saints.” (Jude 3) Clearly, there are many
denominations and many different interpretations of the Bible. Some
different interpretations do not matter, as they are not a matter of
salvation, but some definitely do matter. Two people can differ on the
details of what it will be like when Jesus comes back and still both be
saved. Two people who disagree on who Jesus is or on how to be saved
cannot both be right with God. A possible list of doctrines which are
necessary to be correct on is found in Ephesians 4:4,5. Again, it is your
job is to carefully study out the Bible for yourself and decide whether,
based on your study, you are right on these basic areas of doctrine.

John Oakes, PhD