I see apostasy evidenced in the Christianity of America almost every day as I visit Christian blog sites. How do I know that what I’m seeing is apostasy?

First can Apostasy be defined? Of course there is a definition, but as with all words in scripture it is a translation from another language, and other languages often have more than one meaning. We rely on the language experts within our faith to garner the proper usage based on the original context. We also believe that an all knowing God who sent His Son, who is presented in scripture as the Word of God, is perfectly capable of guarding the truth of the written word which proclaims what He wants us to know about what is important in our relationship with Him.
So without becoming technical, if we go to the Hebrew Scriptures we find our English word Apostasy defined within the context of those scriptures. An example is found in Jeremiah 8:5-7 “Why then has this people, Jerusalem, Turned away in continual apostasy? They hold fast to deceit, They refuse to return. “I have listened and heard, They have spoken what is not right; No man repented of his wickedness, Saying, ‘What have I done?’ Everyone turned to his course, Like a horse charging into the battle. “Even the stork in the sky Knows her seasons; And the turtledove and the swift and the thrush Observe the time of their migration; But My people do not know The ordinance of the Lord.
Apostasy based on a Scriptural definition is denial of or a falling away from God and His plan for our lives.
In the New Testament this condition is understood as Jesus put it in Matthew 24 simply as a falling away. Paul simply called it apostasy in 2 Thess. 2.
The mindset of the churchianity in America tries to do away with any possibility that a born again believer can be given over to this state. Liberals believe that the God of love will save everyone. Conservative believers mostly fall into the once saved always saved camp.
So, who does Jesus say will fall away if teachers claiming eternal security say we can’t? And what does one fall away from? It’s easy to say that this warning applies to someone else like Israel. So is Israel saved today? — not according to the definition of salvation under the New Covenant Scriptures. So how can Israel be the object of this falling away warning if she is far away from Messiah in the first place. She is yet to be saved in God’s plan. What could she possibly fall from? She is already away from God’s plan for her.
Yet, to me it would be hard to accept or teach from scripture a falling away of born again believers simply for the exercise of disobedience or for just falling into a sinful act, as some fundamentalist teach; because sin can be repented of, and God disciplines us for our sinful ways when we are His. So if falling away is being cut off from the Lord and His salvation how could it happen to one who is a believer safely in Christ? It seems that the final act of one who falls would be a denial of Him who is our salvation. Both Jesus and Paul say that if we deny Him He will deny us. This I believe is the only way in which we can actually trample Him under our foot as recorded in Hebrews 6 and 10 and this final state would leave us without hope. But how does this happen — it certainly is not an easy thing to deny our Lord, especially when the Holy Spirit is our teacher and instructor.
Jesus says that he who endures until the end will be saved. What is He asking one to endure in or through? Why would we not endure. I think the answer can be a lifestyle of unrepented sin, which can lead to a strict discipline and Tribulation from the Lord with a purpose of returning one to his devoted state in Christ, but this trial is of our own making, and it could lead to ones final fall or failure to endure.
But consider this — one could also possibly fall due to unexpected Tribulation — not of our own making. Jesus in the context of this statement on falling away is talking about the Great Tribulation period. Many today do not think that God can possibly allow us to experience such terrible suffering as will be occurring during The Tribulation. When this unexpected event comes is that why many will fall?
There is a major hurricane coming into the vicinity of Florida and the east coast right now. The call is to to prepare. Those who do not may lose their lives. In the Scriptures Paul said in Ephesians chapter 6; prepaid for the evil day. Put on the whole armor of God that you may stand in that day. What is the opposite of to stand? — Is it not to fall?