Why was Jesus standing rather than sitting in Stephen's vision?
In Stephen's vision, Jesus stood because the emphasis was that He is alive, raised, ascended, and ready to return quickly to set up the Kingdom, not merely remaining seated. The standing underscores His readiness for that imminent return, while the tribulation still had to run its course.
Les explains that Hebrews 1 and Psalm 110 present Jesus as having sat down at the right hand of the Majesty on high, so the standing in Stephen's vision is not a mistranslation. He directs attention to Acts 3:19-20 and the message being presented to the nation after Jesus' resurrection and ascension: Jesus is alive, God raised Him from the dead, He has been called back to heaven, but He is ready to return right quick and set up the Kingdom. The tribulation would still have to run its course.
Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord;
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