There are a few words that Satan uses to confuse people because of their double meaning in certain contexts; they are:
necessary, required, has to, must, needed, should, etc... (and all their variants).
- necessary1, required1, has to1, must1, needed1, should1
- necessary2, required2, has to2, must2, needed2, should2
= will inescapably exist under some conditions.
Therefore I prefer not to use these words in Meaning 2 because of the trap, but use other phrases to describe meaning 2.
Here is an example of
- evil is not necessary1, and
evil is necessary2.
necessary1 and necessary2 have the opposite meanings in this context.
This blatant ambiguity is the trap that Satan uses to deceive people into committing evil and transgressions, or in justifying transgressions and sins in themselves or others.
The truth is:
Even though evil will inescapably exist under some circumstances, it is never necessary, or in other words, it is never the duty of any one to do it, because there is always a better way if they are willing to do what God commands them.
Therefore, even though evil and error will inescapably exist in certain circumstances, it is necessary for everyone not to engage in it; in other words, it is the duty of everyone not to do evil.
In fact, it is the duty of everyone under all circumstances, without ANY exceptions, not to sin and not to transgress, because those who transgress will be miserable if they do not repent when they are brought to sufficient knowledge of their transgressions, because every transgression of the laws of God is a self-contradiction, and is unnecessary, because there is always a better way, which is to keep the commandments of God, which is to love all as self.
In the words of Jesus:
1 Then said he unto the disciples, It is impossible but that offences will come: but woe unto him, through whom they come!
So even though it is impossible but transgressions will exist under certain circumstances, they are unnecessary for everyone, if they but choose to obey God, for there is always a better way,-- the way God commanded.
And yes, we always CAN do everything that God commands us:
1 Nephi 3:7
7 ... the Lord giveth no commandments unto the children of men, save he shall prepare a way for them that they may accomplish the thing which he commandeth them.
Sin is always unnecessary.
Transgression is always unnecessary.
Because there is always a better way, the way that God commands.