The scriptures warn:
D&C 88:69 Remember the great and last promise which I have made unto you; cast away your idle thoughts and your excess of laughter far from you.
Why cast away your idle thoughts, which principally means casting away your daydreaming? Why cast excess of laughter far from you?
To answer, we recall a similar warning by Joseph Smith: “A fanciful and flowery and heated imagination beware of; because the things of God are of deep import; and time, and experience, and careful and ponderous and solemn thoughts can only find them out.”
So Joseph Smith gives us a great part of the answer. But that is not the whole story if we use a little common sense. All one needs to do is ask oneself, do you even WANT someone with a flowery and heated imagination, or someone easily caught up in the whims of their daydreams, to be given power of the sort we see described in the following verses?
JST Genesis 14:29 And it was delivered unto men by the calling of his own voice, according to his own will, unto as many as believed on his name.
30 For God having sworn unto Enoch and unto his seed with an oath by himself; that every one being ordained after this order and calling should have power, by faith, to break mountains, to divide the seas, to dry up waters, to turn them out of their course;
31 To put at defiance the armies of nations, to divide the earth, to break every band, to stand in the presence of God; to do all things according to his will, according to his command, subdue principalities and powers; and this by the will of the Son of God which was from before the foundation of the world.
Seriously. We wouldn’t WANT a daydreamer or someone with a flowery and heated imagination to be given that sort of power. And god has at least that much common sense himself. So he teaches his children to steer away from becoming such people, as he is determined to lead them to be gods.
God has given men this sort of power in the flesh, as we read of Nephi in Helaman 10. But we can be sure Nephi learned to cast away his idle thoughts and his excess of laughter before god spoke to Nephi from the heavens saying:
Helaman 10:5 And now, because thou hast done this with such unwearyingness, behold, I will bless thee forever; and I will make thee mighty in word and in deed, in faith and in works; yea, even that all things shall be done unto thee according to thy word, for thou shalt not ask that which is contrary to my will.
6 Behold, thou art Nephi, and I am God. Behold, I declare it unto thee in the presence of mine angels, that ye shall have power over this people, and shall smite the earth with famine, and with pestilence, and destruction, according to the wickedness of this people.
7 Behold, I give unto you power, that whatsoever ye shallseal on earth shall be sealed in heaven; and whatsoever ye shall loose on earth shall be loosed in heaven; and thus shall ye have power among this people.
8 And thus, if ye shall say unto this temple it shall be rent in twain, it shall be done.
9 And if ye shall say unto this mountain, Be thou cast down and become smooth, it shall be done.
10 And behold, if ye shall say that God shall smite this people, it shall come to pass.
Yup. You just wouldn’t want a daydreamer or someone led by the whims of loud laughter to harness that kind of power.