(a) A lawyer put the quoted question to Jesus in order to test him. Jesus however, asked him what was written in the law and how he was reading the law. He summarised the law by saying 'You should love the Lord your God and your neighbour as yourself.' Jesus commanded him to go and do that and he would live and be qualified for eternal life, but the lawyer, still wishing to justify himself, asked Jesus who his neighbour was.
Jesus told him, in a parable, how a man who was travelling from Jerusalem to Jericho fell in to the hands of robbers who beat him thoroughly, stripped him and left him half dead. By chance, a priest and later, a Levite saw him and each of them passed him by on the other side. Later, a Samaritan came by and saw the injured man and gave him first aid. He carried him on his beast to an inn and paid an advance for further treatment and care. He also promised to return and offset whatever extra would be spent on him. Then, Jesus asked the lawyer which of the three (who saw the injured man) proved to be neighbour to him. It was the one who showed him mercy, he answered. Then Jesus asked him to go and do likewise.

(b) Christians can show concern for others in the following ways:
(i) Christians should share with others what they have received by God's grace, especially with those in spiritual and physical need This includes the word of God and the physical assets at their disposal.
(ii)They should take care of the sick, the aged and the invalid in the society.
(iii) They should forgive and reconcile with those who offend them, if they sincerely repent.
(iv)True religion is not just by attending services regularly and paying all tithes and thanksgivings, but more by living a practical Christian life and thereby influencing others through exemplary character. Christians should avoid hypocrisy and do good unto others.