Yes, when there is a good reason for something you tell them to do, and when they are capable of understanding that reason, give your children the reason. But they must eventually come to the understanding that obedience has nothing to do with the reason, but with the authority who requires it. If they never learn this lesson, they will disobey whenever it suits them, whether it is you they disobey, or their teachers, or their employers, or the law of the land—or God.
Look at Lev 18 and 19. God punctuates every command with a declaration of who he is.
My ordinances shall you do, and my statutes shall you keep, to walk therein: I am Jehovah your God.
You shall therefore keep my statutes, and mine ordinances; which if a man do, he shall live in them: I am Jehovah.
That’s just two verses. Keep right on reading for the next page or so. “I am Jehovah,” meant, “I have the right to rule over you.” It meant exactly what we say when we tell our children, “Because I am your father (or mother), that’s why!” It is the exclamation point that says, “I mean it!”
Read through those passages some time today. Some of them may open your eyes to areas in which our culture has failed significantly.
You shall fear every man his mother, and his father… I am Jehovah your God.
You shall not swear by my name falsely, and profane the name of your God: I am Jehovah.
You shall not go around as a slanderer among your people, and you shall not stand up against the life of your neighbor: I am Jehovah.
You shall stand up before the gray head and honor the face of an old man, and you shall fear your God: I am Jehovah, 19:3,12,16,32.
I have read that this was part of the covenant ritual, and as such, we are required to do our part in order to receive God’s part—his blessings in this life, and ultimately salvation. If we won’t obey “because he said so,” we won’t enjoy eternal life with that Father, the Ultimate Authority Figure.
Remind yourself today of that lesson you learned long ago about exclamation points. They are used for emphasis and to express strong feelings. God has perhaps his strongest feelings against those who disobey. “Because I said so,” should be good enough for any who claim to be his children, whether we understand or not.
And by this we know that we have come to know him, if we keep his commandments. Whoever says "I know him" but does not keep his commandments is a liar, and the truth is not in him, but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him: whoever says he abides in him ought to walk in the same way in which he walked. 1 John 2:3-6.