Psalm 119:1
The word WALK implies that the growth of being Christian is a forward process, a journey, a daily interactive Christ-centered life.
Undefiled: innocent, perfect, whole, complete, entire, sound; without blemish, what is completely in accord with truth and fact. (Strong's Hebrew #8549)
Paul's prayer for the Colossians, the church in Colosse (in what is now Turkey) gives greater detail of what it means to walk in integrity as believers.
Colossians 1 (Berean Study Bible)
Walking in integrity requires, first of all, that we have faith in Christ Jesus (v 4). Secondly, we need to strive (be hungry and thirsty for more of Him) to be filled with the knowledge of His will in all wisdom and spiritual understanding (v 9).
With the reminder that this letter was written to a group and not an individual the clarifications are to unity within the group, the church, and not per se to the individual, but should still be brought into the understanding of each individual on what it means to be Christian.
Thirdly, walking worthy unto the LORD unto all pleasing (v 10a) means to live in the unity of the Spirit (Philippians 1:27; 1 Corinthians 1:10); being truthful in every good work and increasing in the knowledge of God (Hebrews 13:20, 21).
Fourthly, (v 11) Strengthened with all might, according to His glorious power, unto all patience and longsuffering with joyfulness. Inner strength through the power of Christ. Joyful in our struggles because we have a hope and a reward in Christ.
Fifthly, (v 21-23) And you, that were sometimes alienated and enemies in your mind by wicked works, yet now has He reconciled In the body of His flesh through death, to present you holy and unblameable and unreproveable in His sight: IF you continue in the faith grounded and settled, and be not moved away from the hope of the gospel, which you have heard, and which was preached to every creature which is under heaven.
Unless we are born again according to the Word of God, through Christ, we remain ignorant and unchanged. But IN Christ we are made holy, perfect, without blemish 'in His sight'! To remain in this faith which brought us to Christ, grounded and settled and immovable, we must remain in His Word, daily reading and studying it; praying over it and in it (speaking aloud the Word of God into our lives and the lives of the people around us. Not just people we know either [Ephesians 2:19 "strangers and foreigners"].
Happy and to be envied is the man of integrity, who lives his life, in the law of the LORD.
Psalm 119:1
