How important is it to be correct?

Lately I've heard some pray in public worship on my travels and ending with "in Him, amen." I am never sure what that means, or if it is proper..

To be clear, I know that I am to pray in the name of Jesus (John 14:13). I am baptized in the name of Jesus (Acts 19:5)

I am justified in the name of Jesus (and the Holy Spirit) (I Cor 6: 11) I am to do everything in the name of Jesus (Colossians 3:17)

So.... if I am to do all these things in his NAME, then why would anyone say "In Him"? This puzzles me. I notice it mostly among young people, and it seems very "trendy" for lack of a better word. Are we changing things up just to keep them fresh and modem? If one is to pray in the name of Jesus, what's wrong with actually using the NAME of Jesus?

Perhaps they mean "in God", like our money says "in God we trust." I know we pray TO God, as Jesus taught "our Father, which art in heaven" which is not to Jesus nor is it to the Holy Spirit. We pray to the father. Granted that Stephen says, after seeing Jesus in a vision, "Lord Jesus receive my spirit" but one could argue that was more than your typical prayer (unless you routinely see Jesus in a vision as you pray). Yet the bible in explicit terms says to pray in the name of Jesus.

You might think I am being too picky but when it comes to God can anyone be casual? Try offering strange fire (I mean fire is fire, right?), or doing a good deed like touching the ark before it hits the ground, or simply being "humanly curious" and peek inside the ark like many did (and died). Take some of God's credit, as Moses did when providing water. Believe in God but offer money for the power of miracles (one might think by human wisdom "it doesn't hurt to ask") or well I dunno I am stretching here maybe simply offer a toast to false gods of gold or silver while drinking from the temple implements sanctified for worship (they're just metal cups, right? They aren't special...). It doesn't pay to be casual with God, at least as far as I can see.

James writes don't just say "Oh I am going to do this or that" but instead say "IF the Lord will, we shall live, and do this or that" (James 4:15) Is that the "in Him" they are referring to? God gives us the Holy Spirit (Luke 11:13) is that who the "in Him" is? Do we pray in God's name, or the Spirit's? Show me the passage, help me here, I don't see it.

James also says "let your yes, be yes, and your no, be no." When we pray, if we expect others to pray with us and to be in harmony with us, when we baptize others, when we are justified, when we do everything, if we are to do all these things in his name then shouldn't we use the name of Jesus? It may not be trendy, or hip, or cool, fresh, or modem, but it is CORRECT. Randy