God also says in His Word:
Mar 13:23 But take ye heed: behold, I have foretold you all things.
So has He told us all things or not? Let’s take a look at your verse from Matthew 24:36 to see if we can get a better understanding of it. Pay particular attention to the word “know” in it various verb forms in the text. We will start at verse 32.
Mat 24:32 Now learn a parable of the fig tree; When his branch is yet tender, and putteth forth leaves, ye know (G1097) that summer is nigh:
This is the Greek word γινώσκω = ginosko = to know ( by experience, or effort ; to acquire knowledge, become acquainted with; hence, to come or get to know, learn, perceive.
Mat 24:33 So likewise ye, when ye shall see all these things, know (G1097) that it is near, even at the doors.
Same word: ginosko
Mat 24:34 Verily I say unto you, This generation shall not pass, till all these things be fulfilled.
Mat 24:35 Heaven and earth shall pass away, but my words shall not pass away.
Mat 24:36 But of that day and hour knoweth (G1492) no man, no, not the angels of heaven, but my Father only.
This is a different word εἴδω = oida = to know (intuitively) without effort, to understand. It is subjective, while ginosko is objective. The word “knoweth” in vs 36 is intuitive knowledge, we can know the information with study. Mar 13:23 But take ye heed: behold, I have foretold you all things.
Mat 24:37 But as the days of Noe were, so shall also the coming of the Son of man be.
Mat 24:38 For as in the days that were before the flood they were eating and drinking, marrying and giving in marriage, until the day that Noe entered into the ark,
Mat 24:39 And knew (ginosko) not until the flood came, and took them all away; so shall also the coming of the Son of man be.
Mat 24:40 Then shall two be in the field; the one shall be taken, and the other left.
Mat 24:41 Two women shall be grinding at the mill; the one shall be taken, and the other left.
Mat 24:42 Watch therefore: for ye know (oida) not what hour your Lord doth come.
Mat 24:43 But know (ginosko) this, that if the goodman of the house had known (oida) in what watch the thief would come, he would have watched, and would not have suffered his house to be broken up.
Mat 24:44 Therefore be ye also ready: for in such an hour as ye think not the Son of man cometh.
Mat 24:45 Who then is a faithful and wise servant, whom his lord hath made ruler over his household, to give them meat in due season?
Mat 24:46 Blessed is that servant, whom his lord when he cometh shall find so doing.
Mat 24:47 Verily I say unto you, That he shall make him ruler over all his goods.
Mat 24:48 But and if that evil servant shall say in his heart, My lord delayeth his coming;
Mat 24:49 And shall begin to smite his fellowservants, and to eat and drink with the drunken;
Mat 24:50 The lord of that servant shall come in a day when he looketh not for him, and in an hour that he is not aware of,
Mat 24:51 And shall cut him asunder, and appoint him his portion with the hypocrites: there shall be weeping and gnashing of teeth.
Now, do I believe Christ is returning on 12/21/2011? No, but something will happen on that date we should be aware of. It is mentioned in a number of ancient cultures as an important date. The demons even know this date.