When I was in high school, I had an English teacher who challenged me to do something others in my class were not doing simply because I was kind of bored with the regular stuff we were learning. I am not a genius or anything, so don't think I was "gifted" in some way and they had to accelerate me in my classes. I just finished my work ahead of schedule most of the time because I enjoyed learning. So, in my free class time, she challenged me to learn more about sentence structure and grammar. She taught me how to diagram sentences, taking them apart into the various phrases, sentence parts, etc. In time, I became quite proficient with this study of the written word. You will probably think I am kind of "out there" when I admit we made a game of it! She'd write the most challenging sentences, or find them in some writings of great authors, and then she'd set me loose to figure out the structure. There were a couple of times she stumped me simply because "words" can have different meaning depending on how they are used. Sometimes they might be a verb (an action word), while other times be an auxiliary verb (one that accompanies the action word and adds tense, for example). I think even this task of taking sentences apart to figure out their many parts helped me recognize the value of words and the various aspects of their meaning depending on how they were used. Sometimes we need to really stop to consider the words we speak, hear, or read - simply because we gloss over some pretty important meaning if we don't!
Be alert and think straight. Put all your hope in how kind God will be to you when Jesus Christ appears. Behave like obedient children. Don’t let your lives be controlled by your desires, as they used to be. Always live as God’s holy people should, because God is the one who chose you, and he is holy. That’s why the Scriptures say, “I am the holy God, and you must be holy too.” (I Peter 1:13-16 CEV)
In this passage, there are a lot of "words" which would otherwise be overlooked if we were to just take a cursory read over them. For example, the "action" described in the first sentence is twofold - be and think. Be suggests to us this idea of allow or cause to happen something which doesn't occur automatically. It has the meaning of continuing in or remaining in some fashion - here defined as "alert". So we are called to occupy ourselves with an alertness - a sense of vigilance, readiness, and even caution. The action of thinking straight describes first the action of bringing to the conscious mind what will allow us rational thought which should help to guide our steps. If you hadn't stopped to really think about it, rational thought is not by accident. It is purposeful and accomplished by us bringing to the forefront various sets of "information" we wish to bring to bear to solve the problem or task at hand. Alert minds have a greater capacity for rational thought. If you don't believe me, recount the last time you were a little preoccupied with something else, heard someone talk to you and then answered without really giving it any thought. You might have actually found yourself granting the kids permission to go out somewhere, hang out with some kids you probably would not want them to, or found yourself being stared at by a totally disappointed spouse who looks at you aghast because of the foolishness of your answer!
The next action is that of "putting" our hope in the grace God has extended into our lives. There is something quite engaging in any action which leads us to "putting" anything into it. When we play dominoes with the intent of staying away from the bone pile and being the first one to go "out", we play in a manner which suggest to all those around that we are intent on winning. If we pick up every discard in a game of canasta, making "book" after "book" of cards in order to run up a huge score with each hand we play, most would say we are playing in a pretty cutthroat manner. We are "putting" ourselves into the games we are playing - maybe because we want to "win", or because we simply love the challenge of the games. Either way, we are "engaged" in them. When we are engaged in something, it is evident in our lives. I think this is what is being described here when we are told to put our hope in God's grace - to actually engage in the display of this grace in our lives because it will point others to Christ and it gives a dynamic testimony as to the intensity of God's love for his kids.
The next action suggested is that of behaving. Now, we all know we can "behave" rather well, or we can be a little "risky" in our behavior depending on how the "mood" hits us, right? We find ourselves edging toward obedience when we are surrounded by those who challenge us to behave well, then almost as quickly we can be edging in the opposite direction when no one is looking! Don't believe me? Just remember the last time you cheated on your diet and you will have your proof right there! The next word in our sentence is "like" - behave like obedient children. This is a word which describes relationship we have with Christ - we are children, but the type of children we are to be is obedient. We all know children have a tendency to go one way or another - never perfectly obedient, and usually never perfectly disobedient! There is this "mixture" of behavior. If we truly "put" ourselves into this pursuit of obedience, we will find our actions leaning more toward "perfect obedience" than "occasional, imperfect obedience". Engagement again plays a huge part in the outcome.
At the very end of these actions describing how we should "engage", there is this idea of "disengaging" from something - any actions which are controlled by our own desires. Now, this may not seem significant at first, but when we consider how this passage has developed, realizing the various words used suggest specific actions we are to take in order to edge closer to perfect obedience, we will also see the actions we are to take in order to keep from edging in the opposite direction! The idea of "avoiding" certain actions doesn't come naturally to us, so this is why we are instructed to move toward certain positive actions, and move away from other actions which are not consistent with producing positive outcomes. Our own desires are fickle most of the time - so relying upon them will get us a little closer to the edge of gray areas in our lives - gray being closer to darkness than light! The closer we stay to light, the less we tend to see the outcomes of darkness! Just sayin!