The Apostles were eyewitnesses
of the resurrected Jesus Christ:

Luke 24:36-53 And as they thus spake, Jesus himself stood in the midst of them, and saith unto them, Peace be unto you.
37 But they were terrified and affrighted, and supposed that they had seen a spirit.
And he said unto them, Why are ye troubled? and why do thoughts arise in your hearts?
39 Behold my hands and my feet, that it is I myself: handle me, and see; for a spirit hath not flesh and bones, as ye see me have.
40 And when he had thus spoken, he showed them his hands and his feet.
41 And while they yet believed not for joy, and wondered, he said unto them, Have ye here any meat?
42 And they gave him a piece of a broiled fish, and of a honeycomb.
43 And he took it, and did eat before them.
44 And he said unto them, These are the words which I spake unto you, while I was yet with you, that all things must be fulfilled, which were written in the law of Moses, and in the prophets, and in the psalms, concerning me.
45 Then opened he their understanding, that they might understand the Scriptures,
46 And said unto them, Thus it is written, and thus it behooved Christ to suffer, and to rise from the dead the third day:
47 And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem.
48 And ye are witnesses of these things.
49 And, behold, I send the promise of my Father upon you: but tarry ye in the city of Jerusalem, until ye be endued with power from on high.
50 And he led them out as far as to Bethany, and he lifted up his hands, and blessed them.
51 And it came to pass, while he blessed them, he was parted from them, and carried up into heaven.
53 And were continually in the temple, praising and blessing God. Amen.


Act 1:4-9 And, being assembled together with them, commanded them that they should not depart from Jerusalem, but wait for the promise of the Father, which, saith he, ye have heard of me.
5 For John truly baptized with water; but ye shall be baptized with the Holy Ghost not many days hence.
6 When they therefore were come together, they asked of him, saying, Lord, wilt thou at this time restore again the kingdom to Israel?
7 And he said unto them, It is not for you to know the times or the seasons, which the Father hath put in his own power.
8 But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judea, and in Samaria, and unto the uttermost part of the earth.
9 And when he had spoken these things, while they beheld, he was taken up; and a cloud received him out of their sight.

See also: Acts 2:32; Acts 3:15 Acts 4:33; Acts 5:32; Acts 10:39; Acts 10:41; Acts 13:31;
1 Corinthians 15:4-9; 1 Corinthians 15:15; 1 John 1:2;Acts 22:15; Acts 23:11; Acts 26:16