On the next day the world would crucify Jesus and seal Him in a tomb, and they have not seen Him since. The Greek tense used here indicates that the disciples would "see" Jesus continually. Therefore, He is not referring to the literal appearances that He would make after His resurrection, since they ceased after forty days. Rather, Jesus is stating that He will continue to be seen by His disciples metaphorically even after His death and ascension (cf. Matt. 28:20).
"Because I live, you will live also" - Because our Lord lived sinlessly and would live again after His crucifixion, His followers would be able to live spiritually (i.e., free from bondage to sin) and eternally following the resurrection of the dead.
"At that day you will know that I am in My Father, and you in Me, and I in you" - On the Day of Pentecost in Acts 2, when the Helper came, a new age would begin. The apostles would see more clearly than ever the unity that He, the Father, and they shared. To be in the Son is to be in His body (i.e., the church; cf. Eph. 1:22,23). All who are in the Son are blessed to have Him dwell in them (cf. Gal. 2:20).
In John 14:21 it is reiterated that merely understanding God's commandments is insufficient unless one also "keeps them." "He who loves Me will be loved by My Father, and I will love him and manifest Myself to him" - The revealing (or manifestation) that Jesus speaks of here is not referring to His literal appearances after His resurrection (cf. 14:19). It also is not referring to His second (and final) coming in which "every eye will see Him" (Rev. 1:7). Quite simply it is a reference to the fact that Jesus will show Himself to those who faithfully obey Him; such will see and know Him (spiritually) in a way that the world cannot.
"Lord, how is it that You will manifest Yourself to us, and not to the world?" (John 14:22). The Judas who asked this question was not Iscariot for he had already left the group and was in the process of finalizing his betrayal (cf. 13:30). The question exposes the lack of understanding at this time on the part of Judas (and likely the other apostles). He is still expecting Jesus to manifest Himself as an earthly king in a physical kingdom. This expectation could not be logically harmonized with Jesus' teaching in this context that He would only reveal Himself to His disciples and that the world would soon see Him no more (cf. 14:19).
Jesus replied - "If anyone loves Me, he will keep My word; and My Father will love him, and We will come to him and make Our home with him. He who does not love Me does not keep My words; and the word which you hear is not Mine but the Father's who sent Me" (John 14:23,24).
The answer that Jesus provided to Judas' question was accurate, although it certainly would not have corrected his misconceptions. That, however, was not Jesus' fundamental aim at that moment. He is content to simply reiterate the fact that only those who love God will be blessed by His indwelling.
Jesus then goes on to express the converse of His prior statement. Those who disobey Jesus are defying the Father since it is He who sent Jesus and instructed Him as to what He should speak (cf. 8:28,29).
We will continue studying John 14 in our next daily lesson.