James 1:16,17

Verse 16 - "Do not be deceived, my beloved brethren."

Definition of deceived is someone causing someone to believe something that isn't true, usually for personal gain.  Definition of beloved is is a much loved person.  Definition is a group of close people.

The writer is saying to those who he loves and is close to 'to please no believe a lie.'

Verse 17 - "Every good gift and every perfect gift is from above, and comes down from the Father of lights, with whom there is no variation or shadow of turning."

Anything that is good and positive (emotions, events, people, things, etc) is from God.  That must mean that everything that is bad and negative (emotions, events, people, things, etc) is from the absence of God.  Since God promised to always be there for us, He can only be gone if we push Him away.  In some cases, it isn't us.  It is others, having pushed Him away (because He is a God of choice), who do or say things that are bad.  That then affects us.  Everyone suffers the consequences of their actions, even if they ask forgiveness (which is always granted.)  God is a God of choice, and He wouldn't be fair if He bubble-wrapped us or didn't let us experience our choices.

God is pure Love.  Pure goodness and positiveness.  There is no evil where He is from.  What comes from Him reflects that.  If you worry about temptations, then pray for Him to come chase them away because where He is, there is no temptation.  If you are looking at all the areas of gray, pray for His guidance, for where He leads, there is no variations of what is right.  You have choices and He will always let you know which ones are His will.  You can choose one of those He says is good, or you can go down yet another route.