To say that something is tried and tested means that it has proven in the past to be effective and reliable.
But it may also means that when it was tried and tested for the first time, it didn't quite succeed or meet the expectations.
So it would have gone through a series of trials and testings before it can be stated that it is effective and reliable.
Such was the faith of the apostles. Such was the faith of St. Thomas whose feast we celebrate today.
Though St Thomas was often labelled as the "Doubter", the reality is that everyone who say that they have faith will also have moments of doubts.
But faith that is not tried and test cannot be really called faith, because faith is about believing in realities that cannot be seen or touched or measured.
Let us prepare for our faith to be tried and tested along the journey of life.
But as Jesus said, blessed are we who have not seen and yet believe and put our hope in God.