Christians experience various emotions in prayer meetings, such as boredom, confusion, or agitation, Yet God promised through Isaiah: ‘I will make them joyful in my house of prayer’ (Isaiah 56:7a). The surrounding paragraph, verses Isiah 56:1-8, has enduring significance because Jesus quoted another line from that verse when he cleansed the temple of money-changers and pigeon-vendors: ‘My house shall be called a house of prayer for all peoples’ (Isaiah 56:7c; Matthew 21:13; Mark 11:17; Luke 19:46).
Yet, isolated from its original context, the quotation doesn’t appear to forbid the obvious convenience of last minute on-site shopping for ‘kosher’ temple shekels and doves suitable for use in one’s worship there. After all, for aged Anna the temple had been a house of prayer every day for decades before Jesus was born (Luke 2:36-37). Admittedly, on this occasion Jesus also quoted a line from Jeremiah: ‘you have made it a den of robbers’ (Jeremiah 7:11); and that was plainly relevant because, now once again the temple was doomed to be destroyed as in Jeremiah’s day, and for the same reasons (see Jeremiah 7:1-15). When you think about it, ‘convenient sacrifice’ is a contradiction in terms!
So, let the text speak for itself in both its Old and New Testament contexts. Isaiah promised that God would enable praying people in several important matters. In their:
Access to his house of prayer has been granted even to those previously disqualified under the regime of Moses’ law – namely, outsiders (‘foreigners who join themselves to the Lord’, see Isaiah 56:3-6) and ‘outcasts of Israel’ (Isaiah 56:8, e.g. eunuchs, Isaiah 56: 3-5; Deuteronomy 23:1).
God welcomes these outsiders as worshippers (‘their burnt offerings and their sacrifices’, 7b) and workers (‘to minister to him’, 6). Their acceptance is described as:
 relational – they had ‘joined themselves to the Lord’, Isaiah 56:3, 6 and thereby ‘become one spirit with him’, 1 Corinthians 6:17) and ‘hold fast my covenant’ (Isaiah 56:4-6);
 righteous – ‘they keep justice and do righteousness’ (Isaiah 56:1-2); and
 restful – ‘they keep the Sabbath’ (Isaiah 56:4-6; by ceasing from their own efforts and entering God’s rest, Hebrews 4:10).
When Jesus acted according to this prophecy, such outcasts as ‘the blind and the lame came to him in the temple and he healed them’ (Matthew 21:14). And Mark adds this unique detail: ‘And he would not allow anyone to carry anything through the temple’ (Mark 11:16). Certainly the blind and lame brought massive burdens into the temple; however, they did not take their blindness and lameness back out again! The house of prayer is where one should (in the words of the old gospel song) ‘take your burdens to the Lord and leave them there (Psalm 37:5).
On their way to the temple Jesus’ ‘disciples began to rejoice and praise God with a loud voice’ (Luke 19:35-40); ‘children’ continued the praise by ‘crying out in the temple’ – the house of prayer (Matthew 21:14-16).
* Since ‘in your presence there is fullness of joy,’ ‘therefore my heart is glad and my whole being rejoices’ (Psalm 16:11, 9) – when we pray together (Matthew 18:19-20).