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It is a failing universal in human nature to serve ourselves rather than God.
The Jews were given the Law through Moses and did not keep it.
Acts 7:53 Who have received the law by the disposition of angels, and have not kept it.
By their traditions built around the Law they made it of none effect.
Mark 7:7... in vain do they worship me, teaching for doctrines the commandments of men.
Because they departed from the Law they caused their Messiah, a sinless man who did nothing but good, to be crucified.
Acts 5:13 The God of Abraham, and of Isaac, and of Jacob, the God of our fathers, hath glorified his Son Jesus; whom ye delivered up, and denied him in the presence of Pilate, when he was determined to let him go. 14 But ye denied the Holy One and the Just, and desired a murderer to be granted unto you;
The human nature of those who profess to be Christians is no different from that of the Jews.
Jeremiah 17:9 The heart is deceitful above all things, and desperately wicked: who can know it?
In the time of the apostles there were already Christians who served themselves.
Philippians 3:18 (For many walk, of whom I have told you often, and now tell you even weeping, that they are the enemies of the cross of Christ: 19 Whose end is destruction, whose God is their belly, and whose glory is in their shame, who mind earthly things.)
It was prophesied of Christianity:
Acts 20:29 For I know this, that after my departing shall grievous wolves enter in among you, not sparing the flock. 30 Also of your own selves shall men arise, speaking perverse things, to draw away disciples after them. 31 Therefore watch, and remember, that by the space of three years I ceased not to warn every one night and day with tears.
A falling away from the truth was inevitable:
2 Thessalonians 2:3 Let no man deceive you by any means: for that day shall not come, except there come a falling away first...
2 Thessalonians 2:11 And for this cause God shall send them strong delusion, that they should believe a lie: 12 That they all might be damned (condemned) who believed not the truth, but had pleasure in unrighteousness.
History shows how the Christian Church lost its way, became a State Church, invented a priesthood, embraced false doctrines and began to persecute others in the name of Christ. ‘Christian’ has fought both ‘Christian’ and none-‘Christian’ alike in war after war down the centuries.
The commandments of Christ are clear.
Matthew 22: 37 Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. 38 This is the first and great commandment. 39 And the second is like unto it, Thou shalt love thy neighbour as thyself. 40 On these two commandments hang all the law and the prophets.
Our neighbour includes our enemies.
Matthew 5:44 But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
We are to do to both friends and enemies as we would like them to do to us.
Matthew 7:12 Therefore all things whatsoever ye would that men should do to you, do ye even so to them: for this is the law and the prophets.
We are to be harmless to others in all respects.
Matthew 10:16 Behold, I send you forth as sheep in the midst of wolves: be ye therefore wise as serpents, and harmless as doves.
Philippians 2:15 That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world;
Very few people are prepared to live by these commandments. This should not surprise us for the disadvantages are obvious.
We have the record of the failure of the Jewish nation as an example.
Romans 2:28 For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: 29 But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
Jesus says that the entrance to eternal life is narrow.
Matthew 7:13 Enter ye in at the strait gate: for wide is the gate, and broad is the way, that leadeth to destruction, and many there be which go in thereat: 14 Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.
Luke 13:24 Strive to enter in at the strait gate: for many, I say unto you, will seek to enter in, and shall not be able.
Many who profess themselves to be Christians will be rejected.
Matthew 7:22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? 23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.
We cannot escape the conclusion that a large proportion of those who profess to be Christians are astray from the gospel and doctrines taught by Jesus Christ and his apostles.
Proverbs 14:12 There is a way which seemeth right unto a man, but the end thereof are the ways of death.
We know a tree by its fruits.
Luke 6:43 For a good tree bringeth not forth corrupt fruit; neither doth a corrupt tree bring forth good fruit. 44 For every tree is known by his own fruit. For of thorns men do not gather figs, nor of a bramble bush gather they grapes. 45 A good man out of the good treasure of his heart bringeth forth that which is good; and an evil man out of the evil treasure of his heart bringeth forth that which is evil: for of the abundance of the heart his mouth speaketh.
Jesus lays out the consequences:
Luke 6:46 And why call ye me, Lord, Lord, and do not the things which I say? 47 Whosoever cometh to me, and heareth my sayings, and doeth them, I will shew you to whom he is like: 48 He is like a man which built an house, and digged deep, and laid the foundation on a rock: and when the flood arose, the stream beat vehemently upon that house, and could not shake it: for it was founded upon a rock. 49 But he that heareth, and doeth not, is like a man that without a foundation built an house upon the earth; against which the stream did beat vehemently, and immediately it fell; and the ruin of that house was great.
The ‘plumb line’ we have is the Bible; if ‘Christians’ preach a gospel and doctrine different from that which we find in the Bible, then we know that their profession is false. If their works do not give glory to God, they are not genuine Christians.
Matthew 5:16 Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven.
I hope you have found this helpful.
May God bless you,