“Go to the feast yourselves; I am not going up to this feast, for my time has not yet fully come.” So saying, he remained in Galilee. But after his brothers had gone up to the feast, then he also went up, not publicly but in private.” – John 7:8-10
In the above verse, we read that Jesus tells his brothers (or companions) that he will not be going to Jerusalem for the Feast of the Tabernacles. However, as soon as the companions leave, he goes privately.
Is Jesus not lying here?
The first person to bring this to discussion was Porphyry, a pagan who brought this to the attention of the Church fathers. His argument was something along the lines that since Jesus lied, then he cannot be God.
The difficulty arose from the Church fathers as to how to make sense of the passage. How to explain or should I say, how to make it such that Jesus is not indicted with deception. The word, ‘yet’ was added to make it seem that Jesus was consistent and was not lying to his companions when he said he will not be going up [‘yet’].
However, although the word ‘yet’ was added, it did not escape Christian and non-Christian scholars eyes that the word was added later. The original reading of Jesus in the Gospel was that he will not go to the festival. There are many Christian Biblical-commentaries that attest, and say that the word ‘yet’ was added in order to protect Jesus.
Note: Those missionaries who claim that they have ‘ancient manuscripts’ which has the word ‘yet’ in there is not true. These are the same MSS Christian and non-Christian scholars who attest that they have been tampered with.
A Commentary, Critical, Expository And Practical On the Gospel Of John – John J. Owen, D.D.
S. Go ye up without waiting for me.
I go not up yet. The word translated yet, is not found in several of the oldest and most authoritative copies, and was perhaps added to shield our Lord from the charge of inconstancy of purpose, if not untruthfulness, in going up to the feast, after positively saying that he should not go up. 
Commentary On The Gospel Of St John – Professor of Theology E. W. Hengstenberg D. D.
Instead of … before …, ‘the reading of most authorities’ … but this reading is manifestly an intentional change, introduced by such as thought they could thereby obviate the seeming contradiction upon with Porphyry and others had laid so much stress, charging the Lord with uncertainty and caprice. … Does not harmonize with what precedes. If the Lord had intended definitely to intimate that He would go up later to the feast, He would have said, as we may suppose, ‘Go ye up now to this feast.’ If we take into consideration the whole position in which the brethren stood with regard to Jesus, the style in which He spoke to them from the beginning, we shall be very far from thinking that He made them partakers of His secret, and admitted them to a privity with His design of going up at a later season to the feast. Such a confidence they had not deserved. He that exalteth himself shall be abased. Accordingly, we can do justice to the notion that there is here another specimen of John’s want of precision in language; and to Chrysostom’s supplementary. … 
Cambridge Bible for Schools and Colleges:
8. Go ye up unto this feast] ‘Yet’ is emphatic; ‘this’ is wanting in authority; we should read, go ye up unto the feast.
I go not up yet] ‘Yet,’ though very ancient, is possibly not part of the original text: it may have been inserted to avoid the charge of the heathen critic Porphyry, that Jesus here shews fickleness or deceit, and therefore cannot be Divine. 
A Commentary On the Holy Bible:
8. I go not up yet]
Many ancient authorities omit ‘yet’… 
Given that the above Christian scholars clearly state that the word ‘yet’ was added. Let’s now move forward and see what the academics have to say on the verse.
John Calvin also does not comment on whether Jesus used deception here, but he is straight up admitting that Jesus went up as soon as his brothers left. It is indicative from his commentary that Jesus did lie,
9. And having said these things, he remained in Galilee. 10. And when his brethren had gone up, then he also went up to the feast, not openly, but as it were in secret. 
William R. Harper and George S. Goodspeed comment on the verse, and state that Jesus did not want to go up to the festival with his brothers, but as they left, Jesus went up immediately. Although they do not say anything about him lying, their writing on the verse does suggest that Jesus did lie.
The Gospel of John. Jesus Manifested as the Son of God – William R. Harper and George S. Goodspeed:
2. The situation at the Feast of Tabernacles:
For some time after Jesus remains in Galilee to avoid the murderous hate of the ‘Jews.’ His brothers, who do not really believe in him urge him to go up to the Feast of Tabernacles, which is near, and do in the face of the world the works which would make him known as the Christ. He replies,
‘The world does not hate you as it hates me for testifying to its sins. You may go up at any time. The time for me to go has not yet come.’
But after they have gone, then very quietly, he too goes up to the feast. There the ‘Jews’ have been looking for him; and the people, restrained from open discussion for fear of the ‘Jews’ whisper their varying opinions about him. 
The following academics acknowledge that in the time when Jesus was alive, such tactics of lying or deceiving was completely normal.
Choosing a Bible Translation – John J. Pilch
“In John 7:8, Jesus says he is ‘not going up to this feast’ but in v. 10 he does go. Some ancient manuscript, indeed the best, have ‘not yet going up to this feast.’ On the basis of manuscript evidence itself, deciding which of these two translations should be preferred is a very close call. The NIV reports in its text ‘not yet going up to this feast’ very likely on the basis of the evidence which holds a slight edge. But the judgement might also be made on the basis of the translator’s avowed commitment to the ‘authority and infallibility of the Bible as God’s word in written form.’ The translators believe that the Bible contain divine answers to the deepest needs in humanity. Humankind’s need for truthfulness and honesty is certainly basic. Indeed to choose the other reading (not going up, but then goes up) runs the risk of making it seem that Jesus lies. The scholarly principle that guides the decision to place this in the text and its alternative in a footnote is the value of selecting the ‘harder reading,’ that is, the one that may be embarrassing or seem incongruous. In other words, which is more likely? That the original report was consistent but a later hand added what seems like a lie? Or that the original report contained an apparent deception but later hand removed it as unbecoming to Jesus? Most translations do indeed place this harder reading in the text and the alternative in the footnote. Yet, while the reading is ‘harder’ to the western reader, it is quite normal to the Mediterranean reader whose culture views secrecy, deception, and lying as legitimate strategies for preserving one’s honor and defending one’s life, as Jesus is doing in this situation. In other words, this version is culturally more plausible than the ‘consistent’ readings preferred by other translations.” 
Professor Erik Wielenberg
The final example of divine deception that I will consider appears in the New Testament. In the Gospel of John, Jesus’s brothers encourage him to go to the festival of booths in Judea and ‘show yourself to the world’ (John 7:4). Jesus appears to respond with deceit: Jesus said to them, ‘My time is not yet come, but your time is always here. The world cannot hate you, but it hates me because I testify against it that its works are evil. Go to the festival yourselves. I am not going to this festival, for my time had not yet fully come.’ After saying this, he remained in Galilee. But after his brothers had gone to the festival, then he also went, not publicly but as it were in secret (John 7:6-10)
…some commentators seek to avoid attributing intentional deception to Jesus.
To see that these distinctions will not help Jesus evade the charge of deception here, consider the matter from the perspective of Jesus’s brothers. Given the exchange between Jesus and his brothers, it would be entirely predictable (and reasonable) that the brothers would understand Jesus to be saying that he would not be attending the festival at all, for any purpose.
The most natural interpretation of the episode is that Jesus planned to attend the festival all along but wanted to so in secret. He intentionally gave his brothers the false impression that he would not attend the festival so that he could do so in secret.
In response, I claim that the interpretation of these four episodes according to which each involves divine deception are the most plausible interpretations on offer. … I do not think that we are in a situation in which there are multitude equally plausible interpretations, some of which involve divine deception are more plausible than the others, so much so that we ought to accept them unless and until a persuasive case is made against these interpretations. 
Commentaries on the New Testament: John – Professor Jo-Ann A. Brant
Whereas the synoptic kin try to stop. Jesus from teaching, because he is shaming the family (Mark 3:21), the Johannine brothers goad him into public humiliation. Seems to be acknowledging that they are trying to score points at his expense:
‘My time is not yet come, but your time is always at hand’ (7:6). He then demonstrates frankness of speech by naming the reality of his situation.
‘It is not possible for the world to hate you, but me it hates, because I am testifying concerning it that its deeds are evil’ (7:7), but he withholds the truth when he says,
‘You go up to the festival; I am not going up to this festival, because my [measure of] time has not yet been completed’ (7:8).
Given the forthrightness with which Jesus speaks elsewhere in the Gospel, its absence here is startling, but within the context of the Greco-Roman world, his deception would be considered prudent rather than wrong, Jesus’s speech reveals the quality of the brothers relationship and not his own character. His lack of frankness is prompted by their disingenuous flattery. Given their After saying these things, he remained in the Galilee (7:9). But when his brothers went up to the festival, then he also went up, not openly but in secret (7:10). Once again, Jesus’s stealth offends some modern sensibilities, but within the ancient Mediterranean context, deception can be seen as necessary and admirable. A short-term strategy to mislead in order to achieve a noble end, such as Odysseus’s disguise when he returns home could be worthy of praise. 
From the verse and the academic evidences we have read, it shows that Jesus indeed lied to his brothers.
Also, read Br. Ibn Anwar’s article: ‘Biblical Taqiyyah (Dissimulation)‘, scroll down to read Jesus deceiving his brothers.
 A Commentary, Critical, Expository And Practical On the Gospel Of John [New York: Leavitt & Allen, 24 Walker Street 1860] By John J. Owen, D.D. Page 154
 Commentary On The Gospel Of St John [Edinburgh: T. & T. Clark, 38, George Street. London: Hamilton, Adams, & Co. Dublin: Hohn Roberton & Co] By Professor of Theology E. W. Hengstenberg, D. D., [Berlin] volume 1, Page 380 – 381
 Cambridge Bible for Schools and Colleges
 A Commentary On the Holy Bible [New York The Macmillan Company 1909], Page 787
 Commentary On the Gospel According To John, [Edinburgh: The Edinburh Printing Company, 12, South St David street] By John Calvin, Volume 1, Page 285
 The Gospel of John. Jesus Manifested as the Son of God: By William R. Harper and George S. Goodspeed – The Old and New Testament Student, Volume 12, No. 5 (May, 1891), page 295 – 296
 Choosing a Bible Translation [Copyright 2000] By John J. Pilch Page 22 – 23
 Skeptical Theism – New Essays by Erik Wielenberg Page 243 – 244
 Commentaries on the New Testament: John [Copyright 2011] By Jo-Ann A. Brant page 135