This is a deep subject and I am only touching on it briefly. It is one that has often been coming up recently in my own life and the lives of others that I know. Speaking for myself, I am currently in an hourly job as a "flex" security officer, sometimes working at the same place on the same schedule for two to three weeks, sometimes changing locations or hours daily. In that context, I suppose it is fortunate that I am single, though that has its own drawbacks. (I am fortunate to have a very patient fiancee in another state and a hope of being married, but firm plans to make it a reality remain puzzling.) This was not what I intended when I got two college degrees, one in Russian language and literature and one in computer science. Some would characterize this as failure, plain and simple. The Word of God tells us that with God faithfulness in small things is a big thing. Paul said he did not judge himself because only at Christ's "bema seat" of judgment will we know fully what Christ considers success.
There is preaching available from many ministries about God "having a plan for your life." Some quite unabashedly lead people to believe that this "plan" is invariably for a happy married and family life with financial success and that if your lot is something else you have sinned and God has dropped you from the "success" program. (Or that perhaps you are just too spiritually blind and deaf to follow God's leading along this path of perennial triumph.) Some preach entirely in the opposite direction, that only the path of maximum self-sacrifice and self-denial is a godly direction and that those who are materially happy are either children of the unsaved world or entirely enmeshed in its deceptive clutches. In America, at least, whatever variation you can imagine between those two ends of the spectrum you can probably find it somewhere - although it appears that megachurches preaching the "prosperity Gospel" do better in certain parts of the country.
"To the Word, and to the testimony," as one of the Old Testament Spirit-led prophets put it. What does the whole counsel of God in the Word of God really say? Does God have a plan for every individual's life? Is it, at least generally, the same plan? Is it a pleasant and comfortable plan? I think the question many of us have - not just Americans - is, does God have a foolproof, (or in some of our cases, excuse my language for a moment, a "damned-fool-proof" plan), that we can't wreck by missing an opportunity somewhere along the line? In my opinion - you can consider it humble or not - those last four answers would be: Yes, No, Sometimes, and a very heavily qualified No.
Jesus Christ's own description of Himself as the Good Shepherd, based on the way shepherds in his culture cared for their sheep, very clearly puts forth the idea of individual care and watching over us. John 1:12 and 1 John 3:1, both of which deal with the great love implicit in being called children of God, make it clear that every individual Christian's life is important to God. To see that God does not have the same plan for everyone's life, the quickest and most obvious illustration is in John 21, where the resurrected Jesus tells Peter, "...but when you are old, you will stretch out your hands, and another will gird you and carry you where you do not wish." Peter then thought immediately of John, whom he may have viewed as a favorite of Christ since he had leaned on him at the Last Supper, and asked what plan Christ had for him. Christ refused to tell him, saying, "...what is that to you? You follow Me." I don't know whether Peter will disclose to us in Heaven how he felt when John showed up in Heaven after such trials as being boiled alive in oil and exiled to the bleak rock of Patmos, but clearly John did not get off as easily as Peter suggested he might.
Is God's plan for my life - or for yours - a pleasant and enjoyable plan? For some of us, our own personal circumstances may be stable and comfortable, compared to the next person. Myself, I seem to be one of the healthiest people I know, at least compared to what I have seen others go through. Only once having been in the hospital a few days for pneumonia in 57 years is a record some people would bitterly envy.On the other hand I have known someone whose life caused me to ask, "who ran over the gypsy?" Part of the answer of "sometimes," to this question, is what we consider "pleasant and enjoyable."
To the question of whether God's plan for a person's life is so immutable and unchangeable that, no matter what mistakes we make or opportunities we miss, He will bring the same destiny to pass, I would say no. However, that is a general answer. God's Word is full in many places of promises of His ability to "restore the years that the locusts have eaten." Redemption is His way and His nature and His preference. Some would say His sovereignty requires that He be able to reach the same end and accomplish His will without any obstruction by human opposition or failure to comprehend or obey. My shortest answer to that is Matthew 23:37, where Jesus told the Jewish leaders, "O Jerusalem, Jerusalem, the one who kills the prophets and stones those who are sent to her! How often I wanted to gather your children together, as a hen gathers her chicks under her wings, but you were not willing!" Or, Stephen's sermon to the Sanhedrin later, in Acts 7, including, "You always resist the Holy Spirit; as your fathers did, so do you."
We cannot surprise God. I believe wholeheartedly that He knows the end from the beginning. Whether in His foresight He is able to plan for any contingency, or whether in His independence of time and unfathomable wisdom He is able to make a new plan, I can't say exactly. Perhaps both. I do believe that the most important truth about God having a plan for my life, or for yours, is in (I Peter 1:7): "That the genuineness of your faith, being much more precious than gold that perishes, though it is tested by fire, may be found to praise, honor, and glory at the revelation of Jesus Christ." There is a general sense in which God does have the same plan for every believer's life - and, I believe, for every person, (II Peter 3:9), "not willing that any should perish but that all should come to repentance." That plan is for every one of us to have the greatest and most genuine faith in His character, in His faithfulness, in His nature, that we can possibly have. Yet in fulfilling that plan each of us that reaches Heaven with Him will, while being conformed to His image, also be a marvelously unique rendition of that image. I think the Scriptures are very clear that that is what God wants us always to have in mind, and in our hearts.
(See "About Me")