Time that is lost in carelessness and sin can never be recovered. God can forgive us a wasted life and still take us into His kingdom. But even God cannot give us back our wasted years. Time wasted is time lost forever. It can never be recovered. That is why it is so good to start following the Lord from your youth itself. Our life on earth is very short. So it is essential that you redeem the time, and make use of every opportunity you get to overcome temptation, and to do good to all. Be rooted in humility, purity and love, at any cost. One of these days, when Jesus returns, and we see Him face to face, you should not have any regret over the way you lived after God gave you light. When many believers see Jesus and discover in that day how much He loved them, they will be crushed with sorrow and regret, that they were so half-hearted during their earthly lifetime, even though they enter heaven. May God save you from such regret. Now is the time to think about that and to be wise. Never sell your birthright (spiritual blessing) for a bowl of porridge (pleasure for the body), like Esau did. "Pursue peace with all men and sanctification, without which no-one will see the Lord" (Heb.12:14). "By and by, when we look on His face, we'll wish we had given Him more....."
Our outer man decays every day. That happens automatically. It is God's will however that our inner man should be renewed every day too ( 2 Cor.4:16 ). But that does not happen automatically. Most believers are not being renewed every day, because they do not do the one thing that Jesus said we should do every day - take up the cross ( Lk.9:23 ). To be renewed in the inner man is to partake increasingly of the life of Jesus within. This can come only as we bear in our body the dying of Jesus daily ( 2 Cor.4:10 ). Every single day has its allotted quota of troubles, trials and temptations (as Jesus said in Matt.6:34 ). It is in these trials that we are to bear the cross and die to ourselves, so that each temptation is made to yield some glory for us.
It is not the will of God that we live an up-and-down life (sometimes on the mountain-top, and sometimes in the dumps). He desires that our lives move consistently only upwards - the inner man being constantly renewed. So we must steadfastly set our face to bear the dying of Jesus at every opportunity that we get every day. We cannot get Divine life from the 'excitement' of meetings and conferences. Many deceive themselves that they have become spiritual, because they were emotionally stirred at a meeting or a conference. But growth does not come from merely attending meetings and conferences. Growth comes through faithfully bearing the cross in the ordinary grind of daily life. We cannot go to meetings every day. But because we have temptations every day, we have the opportunity to be renewed every day.
We must seek to live each day then without complaining and grumbling, in simple faithfulness to the Lord, in the daily temptations, recognizing that our lives do not belong to us (for us to do what we like with it), but that our lives belong to the Lord, because He created us and He purchased us. Then we shall experience daily renewal. But just like the decay of our body is not noticeable every day, but only after some length of time, even so the renewal of the inner man also will be noticeable only after a few years. But the renewal itself will take place every day, if we are faithful ( 2 Cor.4:16 ). So be faithful in the little things and the big. You will realize in the end that it was worth it all, to have crucified your flesh ( Gal.5:24 ), put God first, and lived totally for Him.