Born again believers must not think either too highly or too lowly of themselves.
"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; but to think soberly, according as God hath dealt to every man the measure of faith" (Romans 12:3).
"Shall we continue in sin, that grace may abound? God forbid. How shall we, that are dead to sin, live any longer therein? Know ye not, that so many of us as were baptized into Jesus Christ were baptized into His death? Therefore we are buried with Him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life" (Romans 6:1-4).
If we succumb to the temptation to think too well of ourselves, we grieve the God who "resisteth the proud" (James 4:6). Consecrated believers in the Lord Jesus recognize that He is the source and supply all goodness in our lives, and remember His word to the disciples: "Without me, ye can do nothing" (John 15:5). Never is there a place for pride in our hearts, and never can any act of faithful obedience become a source of believing that we are, as my teen-aged daughter says, "all that, and a bag of chips" (or in my jargon, that "we are really something!").
Conversely, we must also not think too lowly of ourselves. God has already performed a profound work in our trusting spirits that has united us to the Spirit of the Lord Jesus. In the present tense, the Bible declares that we are "alive unto God," and "created in righteousness and true holiness" (Romans 6:11; Ephesians 4:24). Failure to remember these and countless other affirmations of who we are in Christ can lead to a self- pitying spiritual paralysis that conflicts with the Apostle Paul's exultation that "if any man be in Christ, he is a new creature" (II Corinthians 5:17).
Christians are to have "no confidence in the flesh." We are also to affirm that we are "not in the flesh, but in the Spirit" (Philippians 3:3; Romans 8:9). We must join Paul in affirming, "I can do all things through Christ which strengtheneth me" (Philippians 4:19). We do God no favors by failing to believe that we are mightily equipped to faithfully trust and obey Him through the Christ who so dyamically indwells us that He is our life" (Colossians 3:4). "I cannot! I can! Through Christ!" This is the sensibility of the believer who thinks neither too highly or too lowly of himself.
"I labor, striving according to His working, which worketh in me mightily."