'May' in the Bible

And let endurance have its perfect result and do a thorough work, so that you may be perfect and completely developed [in your faith], lacking in nothing.

Yet you do not know [the least thing] about what may happen in your life tomorrow. [What is secure in your life?] You are merely a vapor [like a puff of smoke or a wisp of steam from a cooking pot] that is visible for a little while and then vanishes [into thin air].

Do not complain against one another, believers, so that you will not be judged [for it]. Look! The Judge is standing right at the door.

But above all, my fellow believers, do not swear, either by heaven or by earth or with any other oath; but let your yes be [a truthful] yes, and your no be [a truthful] no, so that you may not fall under judgment.

Therefore, confess your sins to one another [your false steps, your offenses], and pray for one another, that you may be healed and restored. The heartfelt and persistent prayer of a righteous man (believer) can accomplish much [when put into action and made effective by God—it is dynamic and can have tremendous power].