Actually, I highly doubt Jesus would speak as you would.
And by you not being invited to do very many funerals would mean that the gospel would not be preached.
My husband has preached at numerous funerals and some of them for people we are pretty sure were unsaved but as I said, we just don't know for sure. So what does he do? He allows others to eulogize the dead and then he goes up and shares the Gospel. He speaks clearly of sin, of judgment, of Christ's sacrifice on the cross, of our chance for redemption and the great hope we have in Jesus. He then leaves the results to God. He has had people saved after these funerals (no raising of hands, no Just As I Am altar call but just people coming to him afterwards and asking for more info and then being saved). It has also given him the opportunity to speak to others outside of the funeral who were there but didn't respond and maybe later they have more questions. It's really been an incredible ministry.
What purpose would it serve to say "Welcome to the funeral of James Smith. He was an evil man and he is now burning in the unquenching lake of fire where there is weeping and gnashing of teeth. Make sure you don't go there!!"? Is that how Jesus spoke to people? I don't see that in Scripture. We address the living - not the dead. As you said, let the dead bury the dead. That person is gone and it is now our job to address those who are living with the truth of the Gospel.
Ofcourse Jesus and Hid disciples and Prophets spoke like that, why do thing people killed them?:BangHead: DAAAAAAAAAAA
Answer, because they made people very angry. Here are just a few examples in scripture.
Mat 23:12 And whosoever shall exalt himself shall be abased; and he that shall humble himself shall be exalted.
Mat 23:13 But woe unto you, scribes and Pharisees, hypocrites! for ye shut up the kingdom of heaven against men: for ye neither go in yourselves, neither suffer ye them that are entering to go in.
Mat 23:14 Woe unto you, scribes and Pharisees, hypocrites! for ye devour widows' houses, and for a pretence make long prayer: therefore ye shall receive the greater damnation.
Mat 23:15 Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.
Mat 23:16 Woe unto you, ye blind guides, which say, Whosoever shall swear by the temple, it is nothing; but whosoever shall swear by the gold of the temple, he is a debtor!
Mat 23:17 Ye fools and blind: for whether is greater, the gold, or the temple that sanctifieth the gold?
Mat 23:18 And, Whosoever shall swear by the altar, it is nothing; but whosoever sweareth by the gift that is upon it, he is guilty.
Mat 23:19 Ye fools and blind: for whether is greater, the gift, or the altar that sanctifieth the gift?
Mat 23:20 Whoso therefore shall swear by the altar, sweareth by it, and by all things thereon.
Mat 23:21 And whoso shall swear by the temple, sweareth by it, and by him that dwelleth therein.
Mat 23:22 And he that shall swear by heaven, sweareth by the throne of God, and by him that sitteth thereon.
Mat 23:23 Woe unto you, scribes and Pharisees, hypocrites! for ye pay tithe of mint and anise and cummin, and have omitted the weightier matters of the law, judgment, mercy, and faith: these ought ye to have done, and not to leave the other undone.
Mat 23:24 Ye blind guides, which strain at a gnat, and swallow a camel.
Mat 23:25 Woe unto you, scribes and Pharisees, hypocrites! for ye make clean the outside of the cup and of the platter, but within they are full of extortion and excess.
Mat 23:26 Thou blind Pharisee, cleanse first that which is within the cup and platter, that the outside of them may be clean also.
Mat 23:27 Woe unto you, scribes and Pharisees, hypocrites! for ye are like unto whited sepulchres, which indeed appear beautiful outward, but are within full of dead men's bones, and of all uncleanness.
Mat 23:28 Even so ye also outwardly appear righteous unto men, but within ye are full of hypocrisy and iniquity.
Mat 23:29 Woe unto you, scribes and Pharisees, hypocrites! because ye build the tombs of the prophets, and garnish the sepulchres of the righteous,