The exhortation to earnestly contend for the faith which was once delivered unto the saints was given because of the prevalence of false apostles in the early church. These false apostles or deceitful workers are also in the church today, transforming themselves into the apostles of Christ. They preach another Jesus, proclaim another gospel, and operate by another spirit - 2 Corinthians 11:4.

Be sure that you are not hypocritical in your walk with God because all religious pretenders and ministers of Satan will eventually be exposed and rejected by the Lord. On the last day, the Lord shall bring all your deceitful works into judgment. False prophets may succeed in seducing their gullible congregation with signs and lying wonders, but they shall surely reap what they have sown. 

There are only two possible destinations that a man may go to after death: either heaven or hell. While addressing the disciples before returning to heaven, Jesus revealed to them where he was going and the way that leads there. Jesus is not one of the ways but the only way to the Father. And since heaven is the dwelling place of God, it means that one must be a follower of Jesus to enter heaven.

Children of God are called to walk circumspectly to escape the traps of the wicked one. Judas was one of the twelve disciples of the Lord Jesus Christ, who was put in charge of the treasury. Obviously, he was saved. Sent with the other disciples, Judas went to preach the gospel to sinners. He dined and travelled every where with Jesus, so one wonders how Satan was able to enter into him.  

Every confessed sin is judged and covered by the Lord so that the devil finds nothing to accuse you of before God. Unfortunately many believers because of ignorance try in vain to cover their sins. It is better to expose your sins on earth before death, otherwise they will follow you to accuse you before God after you have passed on to the other side of eternity where no defendant will ever be acquitted.