Hold Fast

 Peter knew what it was to start out strong, faithful, and determined to follow Christ without wavering or looking to the side. He did not believe that he would EVER deny Christ; whom he loved so dearly!
And yet, He did.
Temptation, doubt, fear even caused him to do just that.

1Peter 4:10 As every man hath received the gift, even so minister the same one to another, as good stewards of the manifold grace of God.
 11 If any man speak, let him speak as the oracles of God; if any man minister, let him do it as of the ability which God giveth: that God in all things may be glorified through Jesus Christ, to whom be praise and dominion for ever and ever. Amen.
 12  Beloved, think it not strange concerning the fiery trial which is to try you, as though some strange thing happened unto you:
 13 But rejoice, inasmuch as ye are partakers of Christ's sufferings; that, when his glory shall be revealed, ye may be glad also with exceeding joy.
 14 If ye be reproached for the name of Christ, happy are ye; for the spirit of glory and of God resteth upon you: on their part he is evil spoken of, but on your part he is glorified.
 15 But let none of you suffer as a murderer, or as a thief, or as an evildoer, or as a busybody in other men's matters.
 16 Yet if any man suffer as a Christian, let him not be ashamed; but let him glorify God on this behalf.

As a child of God - sometimes the path is sweet and good. You think you won't falter for any reason. You are doing the works of your calling/ministry. God is using you to help others and it feels sooooo good! Ministering to them ministers to you.
Then comes the time of temptation, trial, and will of the flesh. Whether it be a need for prestige (Romans 12:3 For I say, through the grace given unto me, to every man that is among you, not to think of himself more highly than he ought to think) or any other sin awaiting you to trip you up. It will not present itself as an ugly thing or evil. It will present itself through what you have always wanted in the carnal mind or wanted to do.
Still, with these things Christ was also tempted. He went through the tests that you face in your life. He simply wants us to know that we can overcome. We can defeat the evil one and  NO WEAPON FORMED ( and it will form ) AGAINST YOU WILL PROSPER! Don't trick yourself into thinking it won't.
Isaiah 54:17 No weapon that is formed against thee shall prosper; and every tongue that shall rise against thee in judgment thou shalt condemn. This is the heritage of the servants of the LORD, and their righteousness is of me, saith the LORD.

The New Testament disciples were tempted and tried. Even Old Testament men and women of God were tested! Loneliness, need for money- perhaps you watched them drop that "dollar", or someone good looking of opposite sex may cross your path and BAM the opportunity to stumble is right there in front of you.
Maybe it is a sin of offense. Someone hurt you and you just don't want to get over it. You pray for their downfall. It just isn't fair for them to get away with it.
Mark 11:26 But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.

Do not suffer in sinful acts. The suffering God is referring to is trials, temptations, and fleshly desires/lusts. He is there to help us overcome by His might, His power through the Holy Ghost; the Comforter.
Revelation 3:3 Remember therefore how thou hast received and heard, and hold fast, and repent. If therefore thou shalt not watch, I will come on thee as a thief, and thou shalt not know what hour I will come upon thee.