But even if we or an angel from heaven should proclaim to you a gospel contrary to what we proclaimed to you, let that one be accused! As we have said before, so now I repeat, if anyone proclaims to you a gospel contrary to what you received, let that one be accursed! (Galatians 1:8-9 NRSV)
Preaching or proclaiming the gospel is a great responsibility. What we preach is important, especially if we proclaim the gospel publically. As Paul says elsewhere we are to watch out life and our doctrine closely (1 Timothy 4:16). It all needs to stack up, what we preach and how we live. This is not because of what man may think of us, but because of what God thinks of us.
We are each responsible and that holds for people and for angelic beings.
We must expect that God will judge our workmanship and measure it by his standards.
If we are found wanting then we shall not know eternal salvation, but eternal damnation.
Preachers and teachers beware! You may fool men, but you cannot fool God!