The same could be said for tackling drills in football, the putting green in golf, and batting practice in baseball. You never get past these things. They are the basics of the game whether you have moved on to 'bigger and better' things or not.
A similar thing could be said about the death, burial, and resurrection of Jesus. You do not move past these things if you are a Christian. You have to keep them before you, and see how Scripture applies them to all of life.
Some Scripture texts express these 'basics' pretty clearly. J.C. Ryle says that "These texts are among the foundation-stones of the gospel." (Jesus, Keep Me Near the Cross, page 58)
1 Peter 2:24 He himself bore our sins in his body on the tree, that we might die to sin and live to righteousness. By his wounds you have been healed.These are our layup drills, our batting practice, our driving range, etc. for the Christian life. These are verses worth our meditation, memorization, and study.
1 Peter 3:18 For Christ also suffered once for sins, the righteous for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit,
2 Corinthians 5:21 For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.
Galatians 3:13 Christ redeemed us from the curse of the law by becoming a curse for us—for it is written, “Cursed is everyone who is hanged on a tree”—
Hebrews 9:28 So Christ, having been offered once to bear the sins of many, will appear a second time, not to deal with sin but to save those who are eagerly waiting for him.
Isaiah 53:5-6 But he was wounded for our transgressions; he was crushed for our iniquities; upon him was the chastisement that brought us peace, and with his stripes we are healed. All we like sheep have gone astray; we have turned—every one—to his own way; and the Lord has laid on him the iniquity of us all.