You will say then, Branches were broken (pruned) off so that I might be grafted in! That is true. But they were broken (pruned) off because of their unbelief (their lack of real faith), and you are established through faith [because you do believe]. So do not become proud and conceited, but rather stand in awe and be reverently afraid. For if God did not spare the natural branches [because of unbelief], neither will He spare you [if you are guilty of the same offense].

Romans 11:19-21 (AMP)

We are not saved by anything we have done, only because of our belief and because of God’s grace are we grafted into His covenant. Do not count on your own strength but give thanks and worship the Lord always for fear of being cut off as unbelievers are.