More than likely you misunderstand Paul.
Philippians 2:12-13
12 Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling.
13 For it is God which worketh in you both to will and to do of his good pleasure.
Compare with this;
Jeremiah 33:8-9
8 And I will cleanse them from all their iniquity, whereby they have sinned against me; and I will pardon all their iniquities, whereby they have sinned, and whereby they have transgressed against me.
9 And it shall be to me a name of joy, a praise and an honour before all the nations of the earth, which shall hear all the good that I do unto them: and they shall fear and tremble for all the goodness and for all the prosperity that I procure unto it.
Does that seem like salvation is going to be lost because of the "fear and trembling"??
No, not really. Seems like a misunderstanding of what working out your salvation with fear and trembling is.