What does the Bible say about dancing? Should we dance at weddings and can we dance with not our spouse? I believe in only dancing for the Lord.
I may be the wrong person to answer this question. I was raised in the Southwestern United States, an area where most congregations of the churches of Christ soundly condemned going to and participating in dances. Men and women (boys and girls, actually) swimming together was also condemned, along with a number of other things that were frowned on as promoting lust. Although I have enjoyed dancing in times past, I was also the one the girls were ready to beat up because at one school dance I spent more time playing chess with their boyfriends, taking them away from the dancing.
The Bible mentions dancing about 26 times. In most of those cases the dancing is a response to some joyous occasion. Occasionally (Eccl 3:4; Ps 30:11; Jer 31:13; Lam 5:15) it is directly contrasted with mourning. In Matt 14:6/Mk 6:22 the daughter of Herodias danced with the apparent purpose of inflaming desire in Herod. There was also some dancing as part of religious ceremonies. This is mentioned in Judges 21:21, Psalm 149: 3 and Psalm 150:4. It appears in most cases except that of the daughter of Herodias that it was spontaneous, and nothing to be compared with the usual concept of dancing, that is people dancing together in a set pattern to music. So the Bible probably doesn't mention dancing as we know it today.
I am not sure what you mean by "dancing for the Lord." If by that you mean a spontaneous expression of joy through movement, then that is pretty much what is described by the Bible when it refers to dancing. However, there is no mention in the New Testament of that being part of the worship of the church, just as offering incense, playing on musical instruments, or offering animal sacrifices are not specified as part of the worship of the church.
Is it wrong to dance at a wedding, or to dance with someone other than your own spouse? If your spouse objects to you dancing with someone else, then it is clearly something to be avoided. Beyond that, the passage that was most often quoted to me as I was growing up was Galatians 5:19-21-"Now the works of the flesh are manifest, which are these; Adultery, fornication, uncleanness, lasciviousness, Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies, Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God." It was said that dancing fell under the categories of lasciviousness and of "revellings, and such like." Some modern dancing certainly does fall under those categories, but not all does. Certainly going to a night club or dance hall may put you in a place you should not be, but people dance in other places, such as at weddings. So this passage does not always apply to dancing.
I came to the conclusion long ago that I must ask a couple of questions before I participate in an activity like dancing. Can I do so without lustful passions being aroused? Even if I can do so, will it allow someone else who would be so affected to justify their failings by my actions? If the answer to the first is no or the answer to the second is yes, then I should avoid any such action, whether it be dancing or something else.