God's acceptance of born again believers in the Lord Jesus Christ involves a two-fold expression of grace.
"He hath made us accepted in the Beloved" (Ephesians 1:6).
"Wherefore we labor, that, whether present or absent, we may be accepted of Him. For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad" (II Corinthians 5:9-10).
Regarding our person and relationship with Him, our Heavenly Father freely and forever receives us as His sons and daughters, as united to the the Son. Nothing can change the inviolable bond given to us when the Holy Spirit birthed us into family relationship with God. Those born again cannot be unborn, as it were, and we will forever sing the anthem of "accepted in the Beloved," to the glory of our Creator and Redeemer. "And they sung a new song, saying, Thou art worthy to take the book, and to open the seals thereof: for Thou wast slain, and hast redeemed us to God by Thy blood" (Revelation 5:9).
The Apostle Paul nevertheless wrote to the Corinthians of an acceptance based on our works - "we labor to be accepted of Him." To the point, this relates not to our person and relationship with God, but, as Paul declared, to "things done." While we ourselves are freely received in Christ, the life we subsequently live is subject to either acceptance or rejection by our Heavenly Father. Those attitudes, words, actions and relatings to Him and others produced by the Holy Spirit and faithful to the Word of God are accepted and affirmed. Those which do not flow from the Spirit in accordance with Scripture are rejected and subjected to our Father's working to eliminate. A holy God could act in no other way, and a holy people would want it in no other way. "Search me, o God, and know my heart; try me and know my thoughts. See if there be any wicked way in me, and lead me in the way everlasting" (Psalm 139:23-24).
Interestingly, both aspects of God's acceptance are matters of grace. Our person is "justified by faith," that is, we freely receive the favor of God in Christ (Romans 5:1). Our works also are based upon a true and living experience of grace. "Let us have grace, that we may serve God acceptably, with reverence and godly fear" (Hebrews 12:28). Grace births us into everlasting favor by uniting us to Christ and enrobing us in His righteousness. Grace also produces the life of godliness to which we are called by providing the indwelling Spirit of Christ as our very life. We had grace at the beginning of our Christian life in order to be born again. We must continue to "have grace" as we live our Christian life in order to think, speak and act as if we are born again. We do well, therefore, to saturate ourselves in the Biblical declaration of a salvation originated, perpetuated, and never to be culminated by freely given glories, provided by a freely given Savior. Thereby are we "accepted in the Beloved," and thereby do we "labor, that... we may be accepted of Him."
"God... hath saved us, and called us with an holy calling, not according to our works, but according to His own purpose and grace, which was given us in Christ Jesus before the world began."
(II Timothy 1:8; 9)
"By the grace of God I am what I am: and His grace which was bestowed upon me was not in vain; but I labored more abundantly than they all: yet not I, but the grace of God which was with me."
(I Corinthians 15:10)
"Every man's work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man's work of what sort it is. If any man's work abide which he hath built thereupon, he shall receive a reward. If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire."
(I Corinthians 3:13-15).
"As ye have therefore received Christ Jesus the Lord, so walk ye in Him."