Ultimate serenity is the coming to rest of all ways of taking things, the repose of named things; no truth has been taught by a Buddha for anyone, anywhere.
The dangers is that every religion, including the Catholic one, says "I have the ultimate truth." Then you start to rely on the priest, the mullah, the rabbi, or whoever, to be responsible for your acts. In fact, you are the only one who is responsible.
As for the search for truth, I know from my own painful searching, with its many blind alleys, how hard it is to take a reliable step, be it ever so small, towards the understanding of that which is truly significant.
The reasons for which 'this' world has been characterized as 'apparent' are the very reasons which indicate its reality; any other kind of reality is absolutely indemonstrable.
The reality of truth is not to be bought, to be sold, to be repeated; it cannot be caught in books. It has to be found from moment to moment, in the smile, in the tear, under the dead leaf, in the vagrant thought, in the fullness of love.
Therefore, be ye lamps unto yourselves, be ye a refuge to yourselves. Hold fast to the truth as a lamp; hold fast as a refuge to the truth. Look not for refuge to anyone besides yourselves.