So ... with your god how do you know that you are right? Conversations with those thought to be imaginary friends are suspect, all men are fail-able, and the bible has lots of errors that are easy to see (e.g., Pi is not equal to three).
Well there are many ways. You can compare your conclusions with scripture (the scripture that applies). I would be wasting my time to compare my actions to OT verses about attacking Canaanites that have not applied for 2000 years and only to Israel. I can pray about it. I can intuitively grasp it from a God centric point of view. I can use the witness of the Holy Spirit. I can use my God given conscience. Btw only a combination is reliable. Any one or two alone will not be reliable. However I have not really been making an I am right argument. Only that the potential to be right at all is possible with God. Without him there is no right which we are to be.
Conversations with what you may think are imaginary but which billions claim are real is not suspect until you can show it is. remember that Christian morality was not to be applied to a state but to an individual. We may vote but we are not to mandate what governments are to adopt. Fortunately smart men have used God as a template for state morality but it does not get mandated by it. So I do little to enforce my morality on others. I just make arguments about it.
The bible does have errors but even it's committed critics like Ehrman admit it is extraordinarily accurate. More so than any book, of any type, in ancient history. There is not even a close second. Almost all errors are known and they amount to less than 5%. Even Ehrman admits this 5% is not core doctrine and the errors are additions not subtractions in almost al cases. We have virtually the entirety of revelation plus a tiny bit.
The fallibility of man is the best possible recommendation for adopting an objective moral foundation. If we ever act as if secularism is true and adopt social Darwinism I hope I am dust long before it happens. We came close with Stalin, Pol Pot, Ceausescu, Hitler, Mao, etc.... and their Social Darwin/Nietzsche/non-theistic Utopias. Did not work out to well.
I will give you my favorite commentary on secular morality. It is a satirical poem but based firmly in secular morality.
Creed on the World
By Steve Turner
We believe in Marxfreudanddarwin
We believe everything is OK
as long as you dont hurt anyone
to the best of your definition of hurt,
and to the best of your knowledge.
We believe in sex before, during, and
after marriage.
We believe in the therapy of sin.
We believe that adultery is fun.
We believe that sodomys OK.
We believe that taboos are taboo.
We believe that everythings getting better
despite evidence to the contrary.
The evidence must be investigated
And you can prove anything with evidence.
We believe theres something in horoscopes
UFOs and bent spoons.
Jesus was a good man just like Buddha,
Mohammed, and ourselves.
He was a good moral teacher though we think
His good morals were bad.
We believe that all religions are basically the same-
at least the one that we read was.
They all believe in love and goodness.
They only differ on matters of creation,
sin, heaven, hell, God, and salvation.
We believe that after death comes the Nothing
Because when you ask the dead what happens
they say nothing.
If death is not the end, if the dead have lied, then its
compulsory heaven for all
excepting perhaps
Hitler, Stalin, and Genghis Kahn
We believe in Masters and Johnson
Whats selected is average.
Whats average is normal.
Whats normal is good.
We believe in total disarmament.
We believe there are direct links between warfare and
bloodshed.
Americans should beat their guns into tractors .
And the Russians would be sure to follow.
We believe that man is essentially good.
Its only his behavior that lets him down.
This is the fault of society.
Society is the fault of conditions.
Conditions are the fault of society.
We believe that each man must find the truth that
is right for him.
Reality will adapt accordingly.
The universe will readjust.
History will alter.
We believe that there is no absolute truth
excepting the truth
that there is no absolute truth.
We believe in the rejection of creeds,
And the flowering of individual thought.
If chance be
the Father of all flesh,
disaster is his rainbow in the sky
and when you hear
State of Emergency!
Sniper Kills Ten!
Troops on Rampage!
Whites go Looting!
Bomb Blasts School!
It is but the sound of man
worshipping his maker.
Steve Turner, (English journalist), Creed, his satirical poem on the modern mind. Taken from Ravi Zacharias book Can Man live Without God? Pages 42-44