Let's first take Luke 12:47 and 48 into context. This is a parable by the Lord.
Luke 12:42-
42 And the Lord said, Who then is that faithful and wise steward, whom his lord shall make ruler over his household, to give them their portion of meat in due season?
43 Blessed is that servant, whom his lord when he cometh shall find so doing.
44 Of a truth I say unto you, that he will make him ruler over all that he hath.
45 But and if that servant say in his heart, My lord delayeth his coming; and shall begin to beat the menservants and maidens, and to eat and drink, and to be drunken;
46 The lord of that servant will come in a day when he looketh not for him, and at an hour when he is not aware, and will cut him in sunder, and will appoint him his portion with the unbelievers.
47 And that servant, which knew his lord’s will, and prepared not himself, neither did according to his will, shall be beaten with many stripes.
48 But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required: and to whom men have committed much, of him they will ask the more.
When Jesus spoke in parables, many times he spoke of our relations to God. The first verse (42) tells us of a Lord and a steward or servant. It is speaking of those who embark in the service of the Lord. This would include all who hear his word and follow after him. Verse (43) speaks of those who when the Lord comes in his second coming he finds them doing his will and serving God and others. Verse (44) tells us that that servant will be blessed. Verse (45) tells us of those who say in their heart that the Lord delayeth his coming and perform wicked acts. Verse (46) tells us that he will receive his reward with the unbelievers. Verse (47) tells us that those who know the Lord's will and rejected it will be punished more than those in verse (48) who knew not the will of the Lord but still committed evil acts. Thus unto whom much is given much is required. Those who are given much and reject it are punished more severely than those who received nothing but did evil deeds.
The often spoke in parables and used scenarios with which the people could more easily understand his teachings. Thus they made more sense to the people he taught. It doesn't mean that they will be literally beaten with stripes but that their reward or status in heaven will be lower and this will weigh heavily upon them when they are brought to a bright recollection of all their evil deeds and know that they were once valiant in the premortal existence.