The concept of time value of money has been claimed by most experts of Islamic economics as something that is forbidden because of the element of riba in it. Although a common understanding of this concept is reflected in some Islamic muamalah covenant which was permissible in Islamic law, for example is the principle of buying and selling greeting, a tough sale to pay (bai bitsaman al ajil), ijara, and ujrah or wage concept in Islam, where all these things can not be separated from the dimension of time is inherently associated with the existing transaction.

It is a wise move if the cost of capital concepts are clearly defined with little awareness of the value of time. Study of fiqh seemed to dominate the legal side, but the development of these problems must be coupled with other tools to become more comprehensive study and representative for a scientific study. Perhaps we can say that this problem still left some ambiguities which should be dealt with scientifically and adequate, because there will be many questions and discussions that motivate the desire and a new effort to re-provide solutions that are relevant to the development of complex semakain era and complex.

The concept of time value of money is the development of theories that there is interest (theory of interest), of the various views of the capitalist economists of all time. In the classical theory of interest is very well known figure who was Smith and Ricardo, they argue that interest is compensation paid by the borrower (borrower) to the lender (lenders) as remuneration for the benefit of the money lent. If the money can be used to generate business, then so if used for loans. Then Bohm Bawerk, Austrian developer Interest Theory, also argued that people will feel happy with the existing goods rather than goods to be obtained in the future. This marginal productivity of the goods is now greater than the marginal productivity of goods for the future (time preference theory).

Generate theory on the basis of psychological outlook is very subjective, so make an understanding of the theory of interest to be wrong. First, some people are not saving because they want more of her savings in the future, but more for specific purposes, such as school, marriage, retirement and more. Second, a lot of wealth accumulation activities intended only for personal satisfiers, prestige or social status had no need of flowers. Also, why many people who do not spend all his current income but save for the future.

Monetary interest in the theory of reasons is in the form of interest payments actions opportunity to profit from lending money. Keynes called it as speculation the motive of the demand for money (liquidity preference). This motif is defined as an attempt to guarantee profits in the days to come. From these theories the concept of time value of money appears. In the western discipline of economics that there is a position formulation rent, wage and interest; (r) L; (w) L; M, where:
- (R) K means the rent for capital
- (W) means the wage for labor
- (I) M means the interest for the money.

Formulation of the above shows that the equivalent of rent or the rent is fixed assets and the asset moves, equivalent wage labor, and interest or interest equivalent is the money. From here seems to us that, it is wrong to put the rent or lease for the money, because money is not a fixed asset like home or mobile assets such as cars that can be leased. Another reason is the consideration of the inflation factor, which is marked by increasing prices and the overall tempo continuously, resulting in declining purchasing power of money or Decreasing purchasing power of money.

Therefore, according to the concept of time value of MONE also (with inflation as an indicator of the amplifier), then the decision is logical interest money instead of the declining purchasing power of money during lent. However, to say the right reasons in the world economy if all that happened was inflation, deflation or without a stable condition. So do not close the possibility that perhaps lent money now (in the economic circumstances of the inflation rate was 10-30% interfal for instance), precisely in the coming year is higher because of the improving economic situation or in a low inflation rate is below 10 %.

Din Islam is syumul and mutakamil promising with all the solutions the world and akhrat, because he designed as a rahmatan lil alamin. Islamic concept of financial instruments (jihaz Maali) never apart from the wisdom and benefits (ifadah). Islamic concept of time value of money is something that is ijtihadi, said that textually ijtihadi had never heard the word time value of money in verse or hadith the Prophet Muhammad, may we lafadz add as similiar is something lafadz nasaa or forward transaction. Therefore need a serious attempt to explore the law of the instrument was later called ijtihad, and as a more specific derivasinya is qiyas instrument. If we observe carefully the concept of time value of money is qiyas jali or she based the naqli proposition sharih (lihad lafadz nasaa in the history of Imam Bukhari Hadith Hadith no. Mukhatashar book of 938 in al-Saheeh).

In principle, Islam really appreciate the time, this is very grounded and should be believed by every Muslim. Hence there are several verses in the Quran Al Karim makes qasm time as an object or an oath by God, like wal ASHR (for period), wadhuha (after time in the morning), wallaili (by night), wannahaari (by time of day), walfajr (after dawn) and others. In a hadith is also advisable to always take the opportunity before coming narrowness (time utility) and the scholars also stressed the importance of time. As an example of a Sayyid Qutb said: "time is life".

There needs to be discussion between the legal separation time of the value that was practiced in the conventional concept of time with the concept of value in a particular transaction in connection mumalah Islamic fiqh, it is intended that the discussion became more wise and right (mushib). If the time referred to in the concept of value by way of the tough relatively more expensive, and the concept of wages (ujrah) which tended to increase from time to time, a practical example that naturally can not be separated from the time value of money. Islam provides a way out (makhraj) to treat the concept of economic value of time with the return on capital as the foundation work, and not the return on money related to the tribal relationship (rate of interest), as a solution to the concept of time value of money in the practice of conventional economic attached to the practice of usury / interest. Where the value of money / wealth generated by a different person in accordance with the contribution, quality, and other types of donated amalah.