We are told to have a reason for what we believe, so sound doctrine and knowing that God’s word is the ultimate source of truth is the “problem” of every believer.
we are also told very clearly not to add to scripture as well.
“For I testify unto every man that heareth the words of the prophecy of this Book, If any man shall add unto these things, God shall add unto him the plagues that are written in this Book” Revelation 22:18-19
Since alien life is not dealt with in the Bible it is not really an issue that affects one’s faith one way or the other.